Boiled Mackerel

Cover boiled mackerel with a sauce made from blanched fennel and butter.

Prepare and clean some mackerel, put them in salted water, and boil until they are done. When they are cooked, drain the mackerel and put them on a hot dish. Blanch some fennel in salted water, and when it is soft drain and chop it finely; put one tablespoonful in half a pint of butter sauce, and serve in a sauceboat with the fish.