Impossible Cheeseburger
["2 lbs. ground beef", "1 1/2 c. chopped onion", "1 1/2 c. milk", "3/4 c. Bisquick", "3 eggs", "1/2 tsp. salt", "1/4 tsp. pepper", "2 to 3 tomatoes, sliced", "1 c. Cheddar cheese"]
["Preheat oven to to 450\u00b0.", "Grease pie plate.", "Cook hamburger and onion; drain fat.", "Spread on pie plate.", "Beat milk, Bisquick, eggs and seasonings.", "Pour into plate over hamburger.", "Bake 25 minutes. Top with tomatoes and cheese and bake another 5 minutes more until cheese is bubbly and melted."]
["ground beef", "onion", "milk", "Bisquick", "eggs", "salt", "pepper", "tomatoes", "Cheddar cheese"]