Potato pie with mushrooms and onions

We need: Potatoes - 500 g  Egg - 1 piece  Butter - 35 g  Flour - 100 g  Salt, pepper Filling: Champignons - 250 g  Shallots - 200 g  Salt, spices - 2 tsp . Cream cheese - 100 g  Cream 20% - 100%  Cheese - 100 g Cooking: Peel and boil the potatoes until soft, mash them in mashed potatoes. Add butter to the puree and mix. Cool the puree and add the egg to it. Stir and add flour. Mix again. Grease the mold with butter, spread the potato dough into a mold, form the bottom and sides. Cut onions and mushrooms into half rings, fry in vegetable oil with salt and spices. Remove from heat and cool. Add cream cheese to the mushrooms, mix, pour in the cream, mix again. Add 50 grams of cheese. Mix it up. Put the filling on the potato dough, smooth it out. Bake for 20 minutes at 180 degrees. After taking it out, sprinkle the remaining cheese on top and bake for another 15 minutes. Served with sour cream! Enjoy your meal!