Beefy Hash Brown Pizza
["5 c. frozen, shredded hash brown potatoes, thawed", "1 (10 3/4 oz.) can Cheddar cheese soup (undiluted)", "1 egg, lightly beaten", "1/2 tsp. salt", "1/4 tsp. pepper", "2 lb. ground beef", "1 medium onion, chopped", "1 (4 oz.) can mushroom stems and pieces, drained", "1 (15 oz.) can pizza sauce", "4 c. (16 oz.) shredded pizza cheese, divided"]
["In a bowl, combine the potatoes, soup, egg, salt and pepper. Spread mixture into a greased 15 x 10 x 1-inch baking pan. Bake at 400\u00b0 for 25 minutes or until lightly browned. Meanwhile, in a large skillet over medium heat, cook the beef, onion and mushrooms until meat is no longer pink; drain. Stir in pizza sauce. Keep warm. Sprinkle 2 cups cheese over hot crust. Spread meat mixture over the top; sprinkle with remaining cheese. Bake 5 to 10 minutes longer or until cheese is melted.", "Yields 6 to 8 servings."]
["frozen", "Cheddar cheese soup", "egg", "salt", "pepper", "ground beef", "onion", "mushroom stems", "pizza sauce", "pizza cheese"]