Cheeseburger Casserole

Cheeseburger Casserole 2 lb. ground beef 1 large onion, chopped ½ cup ketchup 2-3 tbsp. mustard ½ tsp. salt 1½ cups (6 oz.) Cheddar cheese, shredded 1 cup Bisquick 2 cups milk 4 eggs 1 tbsp. sesame seeds, optional Extra ketchup and mustard for serving, optional Preheat oven to 400°F. Spray a 9×13-in. baking dish with cooking spray and set aside. In a skillet, brown and crumble the beef with the onion until meat is no longer pink, drain. Stir in the salt, ketchup and mustard. Spread into the prepared pan. Top with cheese. In a medium bowl, combine the Bisquick, milk and eggs with a wire whisk or a fork until thoroughly combined. Pour evenly over the top of the cheese. Sprinkle with sesame seeds. Bake 25-30 minutes or until a knife inserted near the center comes out clean.