About 8 oz white fish - cod, coley, haddock. Fresh is best,
but frozen is fine.
4 oz frozen peas
4 oz frozen sweetcorn
12 fl. oz skimmed milk
1 heaped tbs plain flour
2 tbs chopped parsley
3-4 medium potatoes (OR 1 sachet instant mashed potatoes)
2 oz cheese (Optional)
If the fish is frozen, thaw it, and chop into small pieces, removing bones and skin. Peel and boil the potatoes, then mash with a little milk and seasoning. Or make up instant potatoes according to the instructions on the packet.
Whisk flour and milk together, and bring to the boil, stirring all the time. When it thickens, add parsley, fish, peas and sweetcorn. Season to taste. Transfer to an oven-proof dish, top with potato and sprinkle with grated cheese, if desired. Bake in a moderate oven for about 40 minutes
For a party, add 6 oz or so of chopped squid to this, or perhaps a tin of crabmeat.
You could make the sauce with a can of chopped tomatoes, liquidised, instead of the milk and parsley. If you haven't much fish, increase the amount of peas and/or sweetcorn. Use other root vegetables (carrots, swedes [rutabaga], parsnips, etc) instead of, or as well as, the potato topping.