Sauté mushrooms in a little butter with shallots, salt and pepper until all liquid evaporates. Cool down.
Sear lamb loin on all sides. Cook rare. Cool down.
Place pastry on lightly floured surface; in the center place 2 tablespoons mushroom mix. Cut a 1-inch square slice of chicken pate and place over mushrooms. Place lamb on top of pate. Enclose pastry around lamb and seal tightly. Invert and brush with beaten egg. Cook in 350° F oven 10 minutes for medium rare.
Slice and serve over your favorite sauce.
Makes: 1