PREHEAT oven to 400° F.
PREPARE cake mix batter according to package directions. Stir in half of chopped Butterfinger. Spoon 2 tablespoons cake batter into each cone. Place cones in the cups of a muffin pan or on a baking sheet.
BAKE for 15 to 20 minutes or until wooden pick inserted in cake comes out clean. Cool completely.
DECORATE with frosting. Sprinkle with remaining chopped Butterfinger. The cones are best served the same day they are prepared.