Though sole is pre-eminently the fish for invalids, other white fish may be used for this dish.
A little lemon-juice.
Salt and pepper.
Skin and fillet the fish. Butter a plate, lay in the fish, cover it with a piece of buttered paper and a lid or second plate. Place it over a saucepan of boiling water, and let it steam until the fish is cooked; it will probably take eight or ten minutes, but this will depend on the thickness of the fillets.
Next break the fish up into shreds, put these in a small pan with any juice there may be on the plate, also the sauce and a dust of salt, pepper, and lemon-juice. Make the mixture very hot; meantime, cut some thin slices of brown bread-and-butter, trim off the crusts, and spread a layer of the mixture on each. Roll them neatly up and serve at once.