It's difficult to feel cheerful at the prospect of spending time in Grosvenor Square. The US embassy looks like Checkpoint Charlie and there are armed police at every corner. The contrast between London's uneasy response to terrorist threat and the blossoming restaurant scene couldn't be greater.
Maze, the most recent opening in Gordon Ramsay's collection, occupies a section of the square. The dining room is a large, dull space, and must have posed problems for his design team. I am not convinced they've been especially successful. But the chef, Jason Atherton, most certainly has. His menu is split into two: a selection of 20 small dishes from which you choose six, eight or 11, and a more traditional arrangement in which you pick a three-course meal from larger versions of some of the same dishes. I chose six small dishes of whatever the chef thought was a good idea.
This proved a smart move, because the order in which the food arrived turned out to be important and the progression from delicate to robust a crucial aspect in enjoying the meal. The idea is to construct a tasting menu tailored to your own preferences and capacity. More important, if you listen to advice you'll still have a soundly structured meal, rather than a Frenchified version of tapas in which an array of mini starters turn up until you are either bored or full.
Lunch began with an extra course, a cocktail glass lined with mackerel jelly over which the waitress poured chilled gazpacho. It was a cute idea, and woke up the tastebuds rather like a Bloody Mary might, the jelly being solid enough to give some texture, separating the fish taste slightly from the tomato-rich soup, yet soft enough to feel part of the overall arrangement.
We followed with marinated beetroot, Sairass cheese, pine nut and cabernet sauvignon dressing. This read, and looked, as if it were going to explode with big, sweet and sour tastes, but it was subdued and subtle, with four lightly marinated beetroot discs wrapped around small chunks of cooked beetroot and cheese. I had not come across the ricotta-like Sairass before and couldn't work out if it was from sheep or cows' milk; the flavour was restrained and nicely in harmony with beetroot that tasted of itself, rather than of the dressing.
Next came lobster with white radish and asparagus in aigre doux dressing. The lobster was at room temperature rather than from the fridge: lobster loses sweetness after cooking and those who dislike it will almost certainly have eaten specimens cooked too long, too far in advance or kept at too low a temperature, any of which destroy what character and charm the meat may have. The dressings and other bits on the plate were unobtrusive, lending texture and seasoning but no more. This sort of cooking calls for skill and good judgment, as well as the humility to leave well alone occasionally. Words such as subtle and delicate live dangerously close to bland and tasteless, and there are fewer chefs capable of carrying off this style when it's called for than those happy to blow your head off with wine reductions and chilli.
A scallop dish with spiced raisin purée and cauliflower changed the style and pace of the meal dramatically. Big flavours and a Middle Eastern feel, with thick slices of scallop coated in salt and spices resting against raisin and purée, gave a confident and powerful fanfare before the meal's one meat course: spring lamb with cinnamon sweetbreads and ras el hanout. The lamb came as a single cutlet roasted rare with lambs' sweetbreads dusted with cinnamon. Ras el hanout is a catch-all name for a spice mix that usually contains such Moroccan favourites as dried rosebuds, cardamom, ginger and nutmeg. The general idea is fragrant rather than fiery. It worked wonderfully here, and the lamb, even just the one cutlet, gave the feel that the meal had reached its central point, hunger satisfied, and that pud would be next.
In fact, two came - a trifle topped with lemon granita and garnished with a mini vanilla muffin straight from the oven, then pineapple carpaccio with ginger lime syrup, coconut sorbet and pink peppercorns. The sorbet's texture was spot on, the pineapple, as you might expect, sliced into the thinnest of rounds.
In keeping with the theme, wines can be bought by the glass, in flights (that is, three different glasses) or by the bottle. The wine waiter chose for us a glass each of Albariño, a crisp but not mouth-puckering summer white from northern Spain, a gewürztraminer to go with the spicy scallops and a soft pinot noir for the lamb. That lot cost £28 for two, which, as well as being a sound idea, was serious value for money. Like everything else about the restaurant, the wine service was approachable and unstuffy.
Maze is not expensive at about £30 a head for the food, which is a snip for the most exciting new restaurant of the year. My expectation is that this idea, concept, call it what you like, will prosper, with imitations turning up in provincial cities in a year or two. This one works because the chef is a real talent and the front-of-house staff are eager that you enjoy the experience. I am not sure how easy it will be to reproduce that winning combination.
Readers' restaurants
What's the best fish and chip shop in Devon and Cornwall? Chinese in Manchester? Tea rooms in Edinburgh? Or north London gastropub? Send a 100-word review of your favourite to Guardian Weekend, 119 Farringdon Road, London EC1R 3ER (restaurants@theguardian.com).