Stew the mushrooms, zucchini, onions and garlic with oil and a little broth. First add the mushrooms and zucchini to the pan and season with salt and pepper. Then add the onion and garlic.
Cut the tomatoes into pieces. When there is almost no moisture in the pan, deglaze with tomato sauce and fresh tomatoes. Turn down the heat. In the meantime or afterwards, fry the tartare.
Place the lasagne plates in a baking dish and alternate layers of sauce and plates. Spread the tartare on the last plate and cover with the rest of the tomato sauce. Then spread the creme fraiche in dots and finally sprinkle with cheese. Bake for about 30 minutes at 180 degrees fan-assisted or 200 degrees gas.
A few tomato wedges with basil leaves as a decoration.