Lightly grease a baking dish and cut the onions into rings. Place the bay leaves and cloves on top and pour the white wine over them. Drizzle the lightly salted and peppered fish fillets with lemon juice and place on the onions.
Cook in a preheated oven (top and bottom heat) at 225 ° C for approx. 30 minutes. If the pieces of fish are very thick, the cooking time can be longer.