Open your mackerel at the back, season with pepper and salt, butter all
over, and lay quite flat on the gridiron, broil it about a quarter of an
hour over a moderate fire, and place it in a dish without a napkin, then
put half a pound of butter in a stewpan, place it over a sharp fire till
it becomes black, (but not burnt,) throw in half a handful of picked
parsley, fry it crisp, and pour it over the fish, then put four
tablespoonfuls of common vinegar into the stewpan, boil it half a
minute, season with pepper and salt, and pour likewise over the fish,
put it in the oven five minutes and serve very hot.