Preheat oven to 350°F. Using pastry brush, grease inside of pan cavities with solid vegetable shortening, vegetable pan spray, or use Wilton Cake Release.
Do not use butter, margarine or liquid vegetable oil. Spread shortening so that all indentations are covered.
Sprinkle flour into cavities, shake to cover all greased surfaces and remove excess flour.
Prepare mix; pour 1/3 cup batter into each cavity in pan. Bake on middle rack of oven for 15-20 minutes.
Cool 5 minutes and trim so cakes sit level. Unmold cakes and cool 30 minutes before decorating.