Clean the onions and garlic and blend them together with the wine, sugar, 1 tablespoon of butter, salt and black pepper to taste, some parsley sprigs and tomato paste. Brush the pieces of rabbit with the resulting sauce thoroughly and leave them for 1 hour, covered with foil.
Clean the potatoes and cut them into a greased tray. Season to taste with a little salt, black pepper and put the bay leaves in. Distribute pieces of marinated rabbit meat on top. If you have marinade left over, pour it into the tray.
Add a glass of warm water. Cover the tray with foil and put it to bake in a moderately heated oven for 1 hour. Remove the foil and bake until it gets a nice tan.