- Sauté the onions in butter or fat until they are translucent and just beginning to brown.
- Add the potatoes and toss until coated with fat.
- Place in a baking pan or in a roasting pan under a partially cooked roast. Pour in the hot stock. Season.
- Bake 1–1½ hours at 350°F (175°C) or at the roasting temperature of lamb, until