1 carp, about 800 g/1¾ lb, or 2 smaller fish
400 g/14 oz potatoes, very thinly sliced
100 g/4 oz onions, very thinly sliced
salt and freshly ground pepper
3 bay leaves
1 sprig of thyme
50 g/2 oz butter, diced
Preheat the oven to 180ºC/350ºF/gas 4. Gut and scale the carp and rinse under cold water. Cut 3 deep slashes in each side of the fish and insert the bay leaves into the slashes on one side. Place the thyme into the cavity and set aside. Mix the potatoes and onions in a bowl. Season with salt and pepper. Transfer to a flameproof dish and pour over 100 ml/4 fl oz water. Cook in the preheated oven for 10 minutes.
Lay the carp on top of the potatoes, arrange the butter around it and cover with foil. Cook gently over low heat for 5 minutes, then place in the oven and cook for 20 minutes if the fish is large (a smaller fish will need less time). The potatoes must be tender and well cooked.
Extracted from Memories of Gascony by Pierre Koffmann. Available here