Clean the mushrooms, wash and possibly halve them. Cut the bacon into cubes. Wash meat and dab dry.
Heat 1 tablespoon of oil in a frying pan. Fry the potato noodles in the pan for about 5 minutes, remove. Heat 2 tablespoons of oil in the frying fat. Season meat with salt and pepper. Fry the meat on each side for about 2 minutes, remove.
Fry the bacon in frying fat for 2-3 minutes. Add butter and melt. Fry the mushrooms for 4-5 minutes while turning. Dust with flour and sauté briefly. Add milk, cream and stock and simmer for about 5 minutes.
Season to taste with salt and pepper.
Grate cheese. Put the potato noodles and meat in an ovenproof dish (approx. 15 x 23 cm, 6 cm deep; 1.5 litres capacity). Spread mushroom-bacon sauce on top and sprinkle with cheese. Casserole in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) bake for 15-20 minutes until golden brown. Wash chives, shake dry and cut into small rolls. Remove the casserole from the oven and sprinkle with chives.