Preheat oven to 400 degrees F. Line twelve 2 1/2-inch muffin cups with foil bake cups.
In a large skillet cook ground beef and onion over medium heat until meat is browned. Drain off any fat. Stir in beans and barbecue sauce.
In a medium bowl combine the next four ingredients (through sour cream); stir in corn. Spoon about 1 tablespoon of the batter into each prepared muffin cup. Top each with about 1/4 cup of the meat mixture and about 1 tablespoon of the remaining batter.
Bake 15 minutes or until golden. Sprinkle with cheese. Bake 1 minute more. Cool in muffin cups on a wire rack 5 minutes. Remove from muffin cups. Serve warm.