Crush the peppercorns, mix well and press into the fillet. Heat clarified butter in a roasting pan, sear the filet briefly on all sides and cook in the oven at 180 degrees for half an hour.
For the gratin, butter a shallow gratin dish, peel the potatoes, cut into thin slices and arrange in a fan shape in the dish. Season well with pepper and salt, pour whipped cream over until the top layer of potatoes is covered. Season with a hint of nutmeg and sprinkle with butter flakes.
Bake in the oven at 200 °C for 25 minutes until golden.
Serve with: chicory salad
By the way: Did you know that clarified butter is obtained by extracting water, milk protein and lactose from butter?