Wash trout thoroughly from the inside. Carefully dab dry and salt only inside. Heat the fat (up to 1/2 tablespoon) in a pan and fry the trout on both sides until golden brown. Wash and clean or peel the vegetables. Cut zucchini, carrots and mushrooms into wafer-thin slices. Halve or quarter the shallots. Bring 1/4 litre water, wine, peppercorns, bay leaf, sugar and 1 level teaspoon of salt to the boil.
Put the vegetables in a greased casserole dish. Place the fried trout on top and pour the hot wine stock over it. Steam in closed form in a preheated oven (electric cooker: 200 °C/ gas: level 3) for about 15 minutes. Peel the potatoes, halve or quarter them and cook them in a little salted water. Drain and toss in the liquid cream. Serve the trout in the vegetable bed in the casserole dish. Add cream potatoes extra