SPRAY 6 half steam table pans (or 1 half pan for trial recipe) with cooking spray; set aside. Mix soup and barbecue sauce in large bowl. Add chicken, mixed vegetables and onions; mix lightly. Pour evenly into prepared pans.
POUR 3 cups of the corn muffin batter over ingredients in each pan; spread to cover completely.
BAKE in 300°F-convection oven for 35 to 40 minutes or until top of each is golden brown and filling is heated through (160°F).