In 10-inch nonstick skillet, melt 1 tablespoon of the butter over medium-high heat. Cook bell pepper and onion in butter, stirring occasionally, about 5 minutes or until tender. Stir in Alfredo sauce, milk, beans, corn and sriracha sauce. Increase heat to high; cook until mixture is thoroughly heated and bubbly, stirring constantly. Spoon into baking dish.