Take some red mullets, dry them well; put in a fireproof dish a mixtue of butter and oil, a few pieces of fennel and two tomatoes cut in quarters, dispose your mullets over these and bake in the oven. Season them with salt and pepper and when cooked remove them to another dish and keep them hot. Add a glass of white wine and a glass of Madeira to the stock in the first dish, and go on cooking till well reduced. Pass through a fine sieve.
Prepare a maître d’hôtel butter (there should be a good amount of lemon juice in it), with this you bind your sauce; see that it is well seasoned and pour it over the red mullets in the serving dish.