Peel the garlic, cut each clove into six and remove the sprout in the middle. Make slits in each medallion using a pointed knife. Insert 6 pieces of garlic into each medallion. Chill in the fridge for 1 hour.
Peel the potatoes and onions and cut them into rounds. Melt the duck fat in a large pan, add the potato and onion and brown them, stirring regularly. Chop