Preheat the oven to 180 degrees. Cut the zucchini into slices and blanch in salted water for 2 minutes, drain and place in a greased gratin dish. Pepper the fillet of beef, fry briefly on both sides and put aside, covered.
Finely chop plenty of garlic and fry in the frying stock, deglaze with sour cream and season the resulting sauce well with salt and pepper. Pour the sour sauce over the zucchini slices, place the beef fillet on top. Finely crumble the feta cheese over it and place in the preheated oven for about 3 - 5 minutes (depending on how the fillet is cooked).
Take out of the oven and sprinkle with plenty of basil leaves. Warm baguette is served with it. You can also choose to have pork loin or ostrich fillet.