3
Meanwhile, in 12-inch nonstick skillet, cook beef and onion over medium-high heat, stirring frequently, about 5 minutes or until beef is thoroughly cooked; drain. Stir in flour until blended. Add broth, salt and pepper. Cook about 2 minutes or until mixture thickens. Stir in frozen mixed vegetables. Fill each muffin cup with about 1/4 cup beef mixture.