Boil the fish as usual, and dish without a napkin; have ready the
following sauce: pick and wash a pint of fresh prawns, pound them in a
mortar with half a pound of fresh butter, and rub them through a sieve;
then put twelve spoonfuls of bechamel sauce (No. 7) in a stewpan, with
twelve of melted butter; place it over the fire, and when it boils, stir
the butter and prawns into it; pour the sauce over the fish, and strew
chopped lobster over.