July's Observer Food Monthly is a vegetarian special, guest edited by Paul, Mary and Stella McCartney. As part of this very special event, OFM sourced a selection of vegetarian recipes from top chefs and celebrities, with everyone from Jamie Oliver to Gwyneth Paltrow contributing their favourites.

For more information on Meat Free Monday visit supportMFM.org; for more on Linda McCartney Foods: lindamccartneyfoods.co.uk

Gwyneth Paltrow's slow-roasted tomatoes

Serves 8

12 vine-ripened tomatoes, cut in half horizontally
2 tbsp olive oil

Preheat the oven to 135C/gas mark 1. In a small roasting pan, toss the tomatoes with the olive oil. Roast the tomatoes, seed-side up, for 3 hours.

Gwyneth Paltrow's grilled courgette with mint and red chilli

Serves 8

5 medium-sized courgettes (each about 227g)
120ml olive oil, divided in half
1½ tbsp red wine vinegar
12 large mint leaves, finely sliced
as much very thinly sliced red chilli as you can handle
coarse salt

Preheat your grill to medium. Cut each courgette in half crosswise and then cut each half into 3mm planks. In a very large bowl, toss the courgette with 60ml of the olive oil. Lay the courgette on the grill and cook for about 4 minutes per side, keeping the heat moderate so you're sweating them and not really giving them a ton of colour. Turn the heat up to high and grill for about a minute more on each side to mark them. Depending on the size of your grill, this may need to be done in batches.

Remove the courgette to a large platter. Whisk together the remaining 60ml olive oil with the vinegar, mint and chilli (I just use the bowl I originally tossed the courgette in). Drizzle this over the courgette, being sure to evenly distribute the chilli, sprinkle with coarse salt, and serve.

Gwyneth Paltrow's bruschetta

Serves at least 8

2 loaves of fresh pane pugliese (or your favourite country-style bread), cut into 2cm thick slices
3 large cloves of garlic, cut in half
good olive oil
coarse salt

Grill the bread over a medium flame for about a minute on each side or until toasted and just barely charred at spots. Rub both sides of the bread with the cut side of the garlic. Drizzle one side generously with olive oil (at least 1½ tbsp per slice). Sprinkle with coarse salt and serve.

Gwyneth Paltrow's aubergine Parmesan

Serves 4

4 small aubergines (about 3cm in diameter) or 3 regular aubergines
coarse salt
250ml unbleached, all-purpose flour
olive oil
85g of your favourite tomato sauce (see my recipe below)
1 large ball fresh mozzarella (about 128g)
basil leaves, small handful roughly torn
finely grated Parmesan (about 70g)

Slice the aubergine into about 8.5mm discs. Sprinkle slices with a small pinch of coarse salt on each side and place in a single layer between two clean kitchen towels. Place a cookie sheet on top and weigh down with something heavy (a few tins of beans or tomatoes will do). Let the aubergine sit for 20 minutes.

Preheat the oven to 180C/gas mark 4. Lightly dredge the aubergine slices in the flour. Heat 6mm of olive oil in a large skillet over high heat. When a pinch of flour sizzles on contact, add the aubergine slices in a single layer, turn the heat to medium-high and cook for about 1½ minutes on each side or until dark golden brown. Drain the aubergine on paper towels and repeat in batches until all of your aubergine is cooked, adding more oil as necessary.

In a 32.5cm x 23cm baking dish, arrange as many slices of aubergine as can fit snugly in a single layer. Top each slice with a small spoonful of tomato sauce, a few small pieces of torn mozzarella, a bit of basil and a dusting of Parmesan. Continue the layers, evenly distributing all the ingredients, until everything is used up.

Bake for 25 to 30 minutes or until the cheese is melting and bubbling and the house smells divine.

*For my simple homemade, never-fail tomato sauce that's always in my fridge …

In a large saucepan, slowly cook 6 cloves of thinly sliced garlic in a couple of tablespoons of olive oil for 5 minutes over a low heat. Add 2 large fresh basil leaves and stir for a minute. Add 2 x 800g cans of whole peeled tomatoes along with their juice and 2 more whole basil leaves. Bring the sauce to a boil, turn down the heat, season with salt and pepper and let it bubble away on low heat for 45 minutes. Cool and refrigerate.

Gwyneth Paltrow's burrata with roasted beetroot

I find that when I'm cooking for my purely vegetarian friends, Italian has the greatest variety of options.

I like to start with room temperature antipasti such as burrata with roasted beetroot, olive oil, salt and mint, or slow-roasted tomatoes with mozzarella.

Below you will find recipes for a room temperature – aka stress-free – Italian dinner party.

Serves 8

5 large beetroot
olive oil
sea salt
3 stalks mint, roughly chopped
burrata cheese

Preheat the oven to 200C/gas mark 6. Wash but don't peel the beetroot and trim off any leafy tops. Place them on a roasting tin or a large piece of foil. Coat them in olive oil and sprinkle generously with salt. Cover the beetroot with foil and bake until tender, 30 to 60 minutes, depending on size of the beetroot.

Leave until they are cool enough to handle and then peel. Cut the beetroot into large pieces. Toss with olive oil, roughly chopped mint and salt and serve with hunks of burrata.

Gwyneth Paltrow's artichokes with basil and mint

Serves 8

8 small artichokes
2 lemons
2 leafy stalks of basil
3 stalks mint
500ml white wine
a drizzle of your very best olive oil

To prepare the artichokes, pull off the tough outer leaves. With a serrated knife, trim off the spiky ends from the top 1cm of each artichoke. Trim the stalks down to about 5cm. As you work, put the cleaned artichokes in a large bowl of water that you have squeezed one of the lemons into (reserve the lemon halves).

Put the artichokes, stem-side down, into a wide pan with the squeezed lemon halves, one stalk of basil and two stalks of mint. Pour the wine and 750ml water over the artichokes. The liquid should come at least halfway up the artichokes (if not, add more in the same ratio). Bring to the boil, turn the heat down low, cover and cook, turning occasionally, until they're tender – up to 45 minutes.

To serve, cut the remaining lemon into wedges and tear the leaves from the remaining stalks of basil and mint into rough pieces. Scatter the leaves over the artichokes, drizzle the whole thing with olive oil and serve.

Gwyneth Paltrow's roasted tomatoes studded with garlic

I made this for Stella last summer when she came to dinner at our summer house on Long Island.

Serves 4

8 tomatoes
extra virgin olive oil
2 cups fresh coarse breadcrumbs
2 cloves, thinly sliced garlic
handful fresh thyme, chopped
spaghetti or linguine as much – or as little – as you feel like
Parmesan cheese, freshly grated
salt and pepper

Cut the tops off 8 tomatoes, rub them with olive oil and put them in a baking dish in a preheated oven, 100C/gas mark ¼ for 2-3 hours. Remove from oven.

Meanwhile, heat 3 tbsp olive oil in a pan and add 2 cups of fresh coarse breadcrumbs. Add salt and toast them in the oil until brown.

Take cooked tomatoes and slide thinly sliced garlic into the cavities, top with breadcrumbs and fresh thyme, put some olive oil, salt and pepper on top and cook again in the oven, this time for 1-1½ hours at 180C/gas mark 4.

Cook spaghetti until done and put in a mixing bowl. Add olive oil, Parmesan cheese and a bit of salt and pepper and mix well. Put pasta into individual bowls and place caramelised and stuffed tomatoes on each portion.

Chrissie Hynde's linguine with portobello mushroom ragu

Red wine and meaty portobello mushrooms give this sauce the flavour of a slow-cooked ragu. I add rosemary, but oregano or thyme would also work.

Serves 4

2 medium portobello mushrooms (about 200g)
3 tbsp extra virgin olive oil
1 medium sweet onion, minced
1 tsp garlic, minced
½ tsp fresh rosemary leaves, minced
salt and freshly ground black pepper
125ml dry red wine, such as Chianti
520g tinned whole tomatoes, drained and chopped
200g wholewheat linguine (no egg)
vegan soy Parmesan, grated

Bring a large pan of water to the boil for cooking the pasta.

Remove and discard the mushroom stems (can be saved to make a mushroom stock), and slice into 5mm thick strips. Heat the oil in a large skillet. Add the onion and garlic and sauté over a medium heat until translucent, about 5 minutes. Add the mushrooms and cook, stirring occasionally, until they are quite tender and have begun to give off some liquid. Stir in the rosemary, and salt and pepper to taste, and cook for 30 seconds more.

Add the wine and simmer until it reduces by half, about 3 minutes. Add the tomatoes and simmer until the sauce thickens, about 5-8 minutes. Adjust the seasonings.

When the water comes to the boil, add salt to taste. Add the linguine. Cook until al dente and then drain. Toss the linguine with the mushroom sauce and divide among 4 individual bowls. Serve immediately with grated soy Parmesan.

Natalie Portman's favourite quinoa salad

Every time we choose not to eat an animal, we affirm our belief against killing, against cruelty, against violence. It can be a reminder, three times a day, of what it means to be human, and to have power over other creatures. Just because we can, doesn't mean we should.

Serves 8

500ml water
1 cup quinoa
5 corn on the cob
4 Persian (or little) cucumbers
1 red onion
20 cherry tomatoes
2 lemons
olive oil
salt and pepper
parsley or dill, chopped, if desired

Boil 500ml of water with 1 cup of quinoa until it is done, drain and put it in the fridge to cool.

Cut the kernels off the corn on the cob and blanch them (put them in boiling water for 5 seconds, then directly into ice water to preserve the colour and crunchiness); strain.

Chop into corn kernel-size pieces the Persian cucumbers, a red onion and the cherry tomatoes, and add to the quinoa.

Dress the salad with the juice of 2 lemons, olive oil, garlic powder, salt and pepper to taste. Add chopped parsley or dill if desired. Best summer salad!

Pink's nutty berry tart

Serves 4-6

60g butter
45g raw oatmeal
3 tbsp brown sugar
3 tsp vanilla extract
6 tbsp crushed almonds
pinch of cinnamon

For the topping:
Tub low-fat Greek yoghurt
fresh berries
agave nectar

Preheat the oven to 180C/gas mark 4. Melt the butter and mix with the oatmeal, sugar, vanilla, almonds and cinnamon to form a crust. Press it down into a small springform tin. Bake for 15 minutes. Set aside to cool completely.

Drain the yoghurt. Put it in a sieve resting on top of a bowl so the liquid can drain, then cover with cling film and put in the fridge for 30 minutes.

When crust is cool, and yoghurt is drained, spread yoghurt on the crust, throw on fresh berries and drizzle agave nectar on top. Voila!

Elle Macpherson's fennel soup

Serves 2

1 cucumber, peeled
2 cups chopped fennel bulb
10 celery stalks, chopped
⅔ cup fresh coriander, chopped
½ cup cucumber unpeeled, chopped
1 medium red, purple or orange pepper , chopped

For the garnish, optional:
½ cup cottage cheese
½ cup avocado, diced

In a blender, blend the peeled cucumber, fennel bulb and celery (if you have a juicer, use that instead). Add 60ml filtered water if your blender is having a hard time "turning over".

Pour into serving bowls and top with coriander, chopped cucumber and pepper. Garnish with a dollop of cottage cheese or yummy avocado.

Jonathan Safran Foer's popcorn

Additional seasoning is gilding the lily, but if you need more – black truffle shavings and Parmesan.

popcorn preferably organic, preferably Baby Yellow Topaz
roasted peanut oil
kosher salt

Coat the bottom of a pan with oil. Add popcorn. Do not put in more kernels than can be in contact with the bottom of the pan at all times, and do not heat the oil before putting in the kernels. (The latter will produce popcorn that is merely really good.) Get the pan hot as hell, shaking it more vigorously than seems right for about 30 seconds to evenly distribute the kernels across the bottom of the pan and coat them sufficiently with the oil. Lift the lid for no longer than it takes to say the longest word you know. This brief introduction of oxygen is essential for reasons I can't explain. For the duration of the cooking process, gently slide the pan back and forth over the burner. Listen to what the popcorn is telling you. When the popping slows to two kernels per second, remove the pan from the heat immediately. The popcorn will continue to pop, so don't yet lift the lid. Once all popping has ceased, pour popcorn into a crystal bowl and salt.

• Eating Animals by Jonathan Safran Foer (Hamish Hamilton, £20)

Sharleen Spiteri's pasta bake

Serves 5

handful of baby tomatoes
olive oil
salt and pepper
1 onion
red, yellow and green pepper
2 garlic cloves, crushed
1 courgette
450g Linda McCartney VegeMince
tin of chopped tomatoes
2 tsp tomato purée
500g pack of penne pasta
cheese sauce

Cut the baby tomatoes in half and bake in a small tray in the oven for 20 minutes with olive oil and salt and pepper.

Chop the onion, red, yellow and green peppers and sauté in pan with olive oil and crushed garlic. Grate the courgette into pan and sauté and add the baked tomatoes into the pan. Add the Linda McCartney VegeMince and a dash of oil. Add the tin of chopped tomatoes, 2 tsp of tomato purée and a pinch of salt. Slow cook for an hour on a low heat.

Boil the penne pasta and cook to al dente.

Take a baking tray and add a layer of pasta followed by some mince and top with cheese sauce. Repeat another 2 times and add salt and pepper.

Bake in the oven at 180C/gas mark 4 for 30 minutes.

Sharleen Spiteri's marinated courgette with pine nuts and Parmesan shavings

Serves 4

3 yellow courgettes
3 green courgettes
80g toasted pine nuts
3 bunches wild rocket leaves
salt and pepper
100g Parmesan shavings

For the dressing:

good balsamic vinegar 50ml
salt and pepper
150ml good olive oil
squeeze of lemon juice

To make the dressing, pour the balsamic vinegar into a large bowl and season with salt and pepper. Whisk in the olive oil and finish with a squeeze of lemon juice.

Slice all the courgettes lengthways on a Chinese mandolin so they are approximately 3mm thick. Place the strips of courgette in a colander, season with a little salt and leave to stand for 7-8 minutes so all the excess water is extracted. When the courgette are ready, place on a paper towel and pat dry. Arrange the courgette equally on 4 large plates, evenly distributing the yellow and green vegetables and making sure to create some height. Sprinkle with the toasted pine nuts and drizzle with the balsamic dressing. Add a layer of the wild rocket leaves and drizzle them with the balsamic dressing. Finish the dish with curls of Parmesan shavings.

Laura Bailey's vegetarian pizza

Serves 2

For the dough:

300g strong flour
½ tsp instant yeast
large pinch salt
170ml water

For the topping:

¼ butternut squash
1 garlic clove
olive oil
salt
2 large red onions
2 tbsp balsamic vinegar
40g soft brown sugar

For the pesto:

40g basil (stalks and all)
40g parsley (stalks and all)
40g mature pecorino
20g toasted pine nuts
100ml extra virgin olive oil
1 garlic clove
100g mozzarella
100g feta
salt and pepper
2 small handfuls rocket
some toasted pine nuts

Preheat the oven to 180C. Start with the pizza dough. Add all the dry ingredients into the bowl of your electric mixer with the dough hook attachment. Slowly add the water. You may need slightly more or less. Allow the ingredients to combine and continue kneading the dough on a low speed for about 10 minutes. Leave the dough in the mixer bowl, cover it with cling film and leave it in a warm place for about and hour.

Now for the pizza toppings. You will only need about a quarter of one butternut squash. Peel it and slice thinly into crescent shapes. Finely slice a clove of garlic. Place both the butternut squash and garlic into a baking dish. Drizzle with olive oil and sprinkle over some salt. Cook in the oven for 15-20 minutes. When the squash is cooked remove from the oven and increase the heat to 200C.

For the caramelised onion peel 2 large red onions and cut each into about 12 wedges. Heat some olive oil in a saucepan, add the onions and allow to brown for about 5 minutes or so. Add the water, balsamic vinegar and soft brown sugar. Bring to the boil, put a lid on the saucepan and reduce the heat. Simmer until most of the liquid has evaporated. You should finish up with sweet, sticky, deep purple onions.

The pesto is super easy. Simply add all the ingredients to a small food processor and blend until you have a vibrant green sauce.

Making the pizzas. Divide the dough into two. Dust the worksurface with flour and, using a rolling pin, roll out each one to about 12-14in rounds. They should be nice and thin. Place each pizza base on a baking tray.

Spread a fine layer of the pesto on each base. On one base add the caramelised onion. You won't need all of it. Then tear the mozzarella and place on the pizza also. On the other base add the butternut squash and crumble on the feta. Season both with a little salt and pepper. Cook in the oven for about 10-12 minutes.

When the pizzas are cooked, serve with a handful of rocket on each and some toasted pine nuts on the butternut squash pizza.