Cut the fish into slices, salt and pepper to taste. Fry in vegetable oil for several minutes on both sides. In the same pan, fry the mushrooms sliced in slices and the onion sliced in half rings.
Remove the skin from a tomato by dipping it with boiling water, cut into rings. Peel and chop the egg into 8 pieces. Cut potatoes into circles. In a high baking dish, put half of the mushrooms, and on top of the fish.
Arrange the potatoes in a circle, put tomato slices on the fish, and eggs between them.
Then put the rest of the mushrooms in the center, pour everything with mayonnaise and sprinkle with grated cheese. Bake in a preheated oven to 180 degrees for 20 minutes.
The fish is ready for the monastery , let it cool slightly and serve.