Cut potatoes, tomatoes and onions into slices, fish slices. Put the potatoes in the baking dish first, then the onion and fish. Salt and pepper a little.
Slice the cheese, finely chop the greens. Grease the fish with sour cream 50 gr, then put the tomatoes and grease another 50 gr. sour cream.
Put the cheese and pour the rest of the sour cream.
Casserole with fish cook at 220 degrees 30 minutes.