The tester: Michelin-starred chef of Corrigan's of Mayfair and Bentley's
He devoured Marks &Spencer's fishcakes
He loathed McCain's oven chips

Battered cod

Sainsbury's Beer-Battered Loins
400g, £3.99

The batter is light and delicate and the fish is thick. It tastes fresh and flakes like proper cod. A little greasy, but not bad.
3 stars

Marks & Spencer
130g, £1.29

The batter is top-notch, but it looks like a chicken escalope. They have been mean with the fish - in fact, there's more batter than cod - and the grease from the batter prevails. But it's the lightest of the lot.
2 stars

Waitrose Icelandic
300g, £2.59

The coating is pretty bad. Undercooked and burned, which means it's padded out with egg. The fish isn't spectacular either. There are also a few bones in here.
2 stars

Young's
500g, £3.99

The batter looks lovely, but as soon as you press it, the grease comes out. The fish doesn't taste that fresh either. Best for looks, worst for freshness.
2 stars

Fishcakes

M&S, Gastropub Lochmuir Salmon with Lemon Butter
430g, £4.29

Heavy on the fish and not on the potato. How it should be. The salmon is lovely and flaky and light, flavoured with capers and seasoning.
4 stars

Waitrose Salmon & Dill
230g, £2.59

Potato that tastes like its been boiled up in aquarium water and then covered in breadcrumbs. Over-crumbed and over-seasoned.
2 stars

The Co-operative, Truly Irresistible Smoked Haddock & Gruyère 260g, £1.99

This one tastes of smoked potato. I'd like more fish and a little more flavour.
2 stars

Sainsbury's, Taste the Difference Cod and Cheddar
230g, £2.49

This one looks and tastes like a cheesecake. White mush . Barely any fish, and the coating has been over-egged so it just cracks.
No stars

Oven chips

M&S, Gastropub 400g, £1.99

The only chips that taste like chips. They feel dense and taste like potato. Very gastropub. Not quite home-made standard, but not bad for frozen chips.
4 stars

Rooster 1kg, £1.45, widely available

Light and fluffy; just a bit healthy-tasting. You can't skimp on fat and frying with chips, and even oven chips need fat to cook. They look OK, they're just a bit bland.
2 stars

Tesco, Finest Chunky 1.5kg, £1.68

Dead man's fingers. Old and dry. Like the ones we used to get at school. On the plus side, at least they aren't thin-cut fries.
1 star

McCain
907g, £1.69, widely available

These have been stripped of all flavour and soul. They're slim and dry and crunchy and bland. There's hardly any potato inside. They're hollow like little potato whistles.
No stars

Mushy peas

M&S
50g, 49p

Minty. That's a first. Not authentically mushy marrowfat peas, but as a minty pea mush, very nice. More of a purée than a mush.
4 stars

The Co-op
300g, 35p

These look the best and have the best consistency. Off-green, nice and thick, not too runny. They're just very, very sweet and a bit tasteless.
2 stars

Sainsbury's
300g, 28p

Very sweet mushy peas that are neon in colour and taste of pretty much nothing. Insipid and sweet. Need a lot of seasoning to save these ones.
1 star

Asda
300g, 19p

It's like a swamp landed in a bowl and called itself mushy peas. I mean, strictly, yes, it's the right colour but it tastes like watery, rundown pea water.
No stars

Tartare sauce

Sainsbury's, Taste the Difference
170g, £1.36

Dense and chunky. The herbs and capers look almost hand-chopped. Slightly over-vinegared, but light, creamy and very passable.
4 stars

Asda, Extra Special
175g, £1.22

Riddled with mustard. More like horseradish sauce. But finely blended herbs. More mayo than flavour, and rather acidic.
2 stars

The Co-op
170g, 99p

This is mayo, mayo and not a lot else. Where are the capers and cornichons? Post-recession tartare sauce.
1 star

Tesco
160g, £1.22

It looks homemade. But it has an odd, jelly-like consistency. Yuck. Creamy, yolky nothingness.
No stars

• Corrigan's of Mayfair, 28 Upper Grosvenor Street, London W1, 020 7 499 9943.; Bentley's Oyster Bar & Grill, 11-15 Swallow Street, London W1, 020 7734 4756