Wash and peel the asparagus and cut off the woody ends. Cook the asparagus in boiling, lightly salted water covered with 1/2 teaspoon sugar for 15-20 minutes
Clean, wash and slice the mushrooms. Peel and finely chop the onion. Wash, quarter, seed and finely dice the tomato. Grate cheese finely
Lift out the asparagus and keep the stock. Sauté onion in hot butter until translucent. Fry the mushrooms in it. Dust with flour and sauté briefly. Stir in milk and 1/8 l asparagus stock. Bring to the boil and simmer for about 5 minutes. Melt half the cheese in the sauce. Season to taste with salt and pepper
Toast roasting. Place on a tray lined with baking paper. Cover with 2 slices of turkey breast and 1/4 of the asparagus. Spread the sauce over them. Sprinkle with tomato cubes and the rest of the cheese. Bake in a preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for 12-15 minutes. Wash the chives, chop finely and sprinkle over the top.
Drink: cool white wine