Divide the fish into 4 servings. Wash the lemon with hot water and rub the peel, set aside. Squeeze out the juice and sprinkle it over the fish, lightly salt and pepper on both sides.
Halve the onion and cut into thin slices. Clean the bell pepper and fennel and cut into 1 cm squares or strips.
Heat 1 tablespoon of olive oil in a saucepan. Sauté the onion slices in it. Add the pepper pieces and fennel strips, sauté for approx. 2 minutes. Then pour the vegetable stock and simmer for 10 minutes over a mild heat.
Meanwhile, brush a coated pan with a little oil. Place the fish fillets on the skin side and fry them for about 3 minutes on each side over medium heat.
Add the sour cream and lemon zest to the vegetables, season with salt and pepper.
Divide between 4 plates and serve the fish on top. Sprinkle with chopped fennel greens or dill and garnish the fish with a little horseradish if you like.
A wild rice mixture (50 g per person on a diet) or jacket potatoes (2 small per person on a diet) tastes good with it.
Note: If desired, half of the vegetable stock can be replaced with dry white wine.
Fennel opponents should also try the recipe once - the essential oils are softened by the steaming.