Wash the lamb fillet and cut it into medallions of about 3 cm thickness. Press the meat slightly flat. Fry in 2 tablespoons of hot butter on each side for about 1-2 minutes, then salt and pepper. Remove from the heat immediately and place in an ovenproof dish.
For the horseradish crust, toast the toast and grate finely. Mix well with the horseradish, egg yolk, parmesan cheese and cream. Season to taste with salt and pepper.
Spread the horseradish mixture evenly on the medallions, place rosemary sprigs on top and bake in a preheated oven at 220 °c for approx. 12-15 minutes. For this we made green potato puree with broccoli florets !