In a skillet, brown ground beef, onion, salt and pepper; drain. Spoon half of the ground beef mixture in a 9x13-inch baking dish. Top with half of the sauerkraut and half of the noodles. Repeat layer. Combine soups and milk, pour over noodles. Cover and bake at 350 degrees for 30 minutes. Remove from oven and sprinkle with cheese, return to oven for 20 more minutes. Makes 4-6 servings.