Wash the plaice fillets, pat dry, cut into pieces, rub with lemon juice and salt.
Heat the butter in a saucepan, leave out the ham, add the apple pieces and stew for 2 minutes. Pour the fish stock on top. Mix the flour with the cream and stir into the fish stock, bring to the boil until the sauce is creamy.
Add the fish, capers, cheese and drained asparagus and let simmer for 5 minutes, season with lemon juice, sugar, salt and pepper. Arrange the fricassee and sprinkle with dill.