Philly Beef and Cheese Sandwich

Philly Beef and Cheese Sandwich
1 medium bell pepper, cut into strips
1 medium onion, thinly sliced
4 cups Original Bisquick® mix
2 cups milk
2 tablespoons mayonnaise or salad dressing
2 eggs
1/2 pound thinly sliced cooked roast beef
1/2 pound sliced Swiss cheese
Heat oven to 350°. Grease bottom and sides of rectangular baking dish, 13x9x2 inches, with shortening. Spray 10-inch skillet with cooking spray; heat over medium-high heat. Cook bell pepper and onion in skillet, stirring occasionally, until tender; remove from heat. Stir together Bisquick, milk, mayonnaise and eggs. Pour half of the batter into baking dish. Top with half of the beef, the bell pepper mixture and three-fourths of the cheese. Top with remaining beef. Pour remaining batter over beef. Bake uncovered 35 to 45 minutes or until golden brown. Top with remaining cheese. Let stand 5 minutes before cutting.