1Heat oven to 350°F (325°F for dark or nonstick pans). Place Reynolds Baking Cups in each of 24 regular-size muffin cups.
2Make and bake cake mix as directed on box for 24 cupcakes. Cool in pans 10 minutes; remove from pans to cooling rack. Cool completely, about 30 minutes.
3In medium microwavable bowl, microwave baking chips on High 30 seconds; stir until melted. If necessary, microwave 15 seconds longer. Stir until smooth; cool 5 minutes. Stir in frosting until well blended.
4Immediately spread or pipe frosting mixture on cupcakes. Sprinkle with cinnamon. Store loosely covered.