Why do my fishcakes fall apart?

A fishcake is held together by starch and a little egg, and every failure is something interfering with one of those. Buttery, milky mash is delicious and structurally useless. Waxy potatoes never release enough starch. And a warm, freshly shaped cake has nothing set inside it, so it slumps the moment it meets a hot pan.

What you'll need

• Floury potatoes — Maris Piper, King Edward, Rooster
• Cooked fish, flaked
• Egg
• Flour and breadcrumbs for coating

Step by step

1. Use floury potatoes and dry the mash out.Maris Piper, King Edward or Rooster. Boil in their skins or steam them, drain, then return to the dry pan over low heat for a minute or two to drive off steam. Mash with nothing added — no butter, no milk, no cream.
2. Cook the fish separately and drain it hard.Poach, bake or steam it, then let it cool and drain on kitchen paper. Wet fish is the second largest source of moisture. Tinned fish should be drained and pressed; smoked fish poached in milk should be lifted out and left to steam dry.
3. Flake, do not shred.Break the fish into decent flakes with your fingers, feeling for bones as you go. Fish blitzed in a processor turns to paste and the fishcake becomes dense and rubbery rather than light.
4. Work to roughly equal weights of potato and fish.Half and half is a good fishcake. More fish and it will not hold; more potato and it stops tasting of fish. If you are unsure, err slightly towards potato the first time.
5. Bind with egg yolk, not whole egg.One yolk per 500g of mixture. The white adds water and makes the mixture looser; the yolk brings the fat and lecithin that actually binds. Add flavourings — parsley, spring onion, capers, lemon zest, mustard — but keep anything wet to a minimum.
6. Shape them and chill them, properly.Firm patties about 2cm thick, pressed flat rather than rounded. At least 30 minutes in the fridge, an hour is better, or 15 minutes in the freezer. This is the step people skip and it is the one that matters most.
7. Coat dry, wet, dry.Seasoned flour first, then beaten egg, then breadcrumbs — panko for the best crust. The flour layer is what gives the egg something to grip; going straight to egg on a damp cake is why coatings slide off.
8. Chill again after coating if you have time, then fry in a moderate pan.Shallow-fry in about 1cm of oil over medium heat for three to four minutes a side. Too hot and the crust burns before the middle heats; too cool and the cake absorbs oil and softens. Turn once, with a fish slice.

Tips

• Smoked haddock and mashed potato is the classic combination because smoked fish is drier and more strongly flavoured, so it survives being cut with potato.
• Fishcakes freeze extremely well once shaped and coated. Freeze them on a tray, then bag them, and cook from frozen at a slightly lower heat for longer.
• A tablespoon of mashed potato held back is useful insurance — if the mixture feels loose when you shape the first one, work it in.
• Leftover mash from a previous meal is usually too buttery. If that is all you have, add a spoon of plain flour or a handful of breadcrumbs to the mixture to soak up the fat.
• Salmon fishcakes benefit from something sharp against the richness — capers, gherkin, mustard or plenty of lemon zest.

Common mistakes

• Using leftover buttery, milky mash — Fat and liquid coat the starch granules that are supposed to glue the cake together. It tastes excellent and collapses in the pan, and no amount of extra egg fixes it.
• Skipping the chill — A freshly shaped fishcake has no structure at all. Chilling firms the fat, lets the starch set and lets the breadcrumbs adhere. Thirty minutes in the fridge is the difference between a fishcake and a mess.
• Adding whole egg to loosen a stiff mixture — You are adding water to a moisture problem. If the mixture is too stiff to shape, that is usually fine — stiff shapes badly but cooks well. Loose is the failure.

If it doesn't work

Questions people ask