Shepherd's Pie Supreme

Place lamb on rack in roasting pan. Insert meat thermometer, being careful not to touch bone. Roast uncovered in preheated 300 degree oven 2 1/4 hours or until thermometer registers 170 degrees F. for rare lamb. Cool slightly; trim and discard outer skin, fat and cartilage. Chop or hand grind meat by putting it through coarse blade of meat grinder. Makes about 4 C. ground lamb. Put chicken in saucepan; cover with undiluted chicken and beef broth. Cover and simmer about 3/4 hour or until tender. Cool on plate; reserve stock. Strip meat from bones; put through coarse blade of meat grinder. Makes about 2 C. ground chicken. Combine lamb, chicken, dill, salt and pepper in bowl. Mix well with hands. Dilute mushroom soup with about 1 C. chicken stock, Worcestershire sauce and onion juice. Mix well with meat mixture. Divide mixture in half. Butter 2 two-quart casseroles. Press mixture into each casserole. For topping: Heat water and stock together until boiling; remove from fire. Add milk and butter; stir in potato flakes, beating until light and fluffy. Add sour cream, chives, caraway seeds, salt and pepper; blend well. Top meat in each casserole with whipped potato mixture. Bake in preheated 450 degree oven 20 to 25 minutes. Run under broiler to brown.