Have your fishmonger gut and scale the fish. Wash quickly, wipe dry. Salt and pepper inside, add 1/2 tablespoon of fennel seeds. Rub with salt. Arrange a bed of fennel branches in an ovenproof dish or the dripping-pan of your oven. Use a knife to make two deep slits on each side of the fish, rub them with olive oil, place the fish onto the fennel bed. Cover with a few slices of lemon, bake in a moderate oven (350F), preheated 15 minutes beforehand. Bake for 20 to 30 minutes according to the size of the fish. Do not turn them. Meahwhile, add the remaining fennel seeds to the oil, heat in a double boiler with the juice of 1 lemon, salt and pepper. To serve, slide the fish onto the serving dish, serve the hot oil in a sauceboat with halved lemons.
