When it comes to sprinkles, my cake-decorating cabinet runneth over. I’m always picking up a bottle here and there—at grocery stores, home goods supplies, specialty shops, you name it. I’m drawn to them because I love party cakes, and, if you ask me, nothing says “party” like rainbow sprinkles.
This confetti cake is sprinkled inside and out. A generous 1/3 cup of rainbow sprinkles goes straight into the batter, and then after baking and frosting, it gets a coating of sprinkles on the outside. I love slicing this cake. With all the random sprinkles throughout, you get a unique piece each time! (Please note that you’ll have a little leftover batter after portioning out the 3 1/2 cups needed for the cake roll, so I used the extra to make 6 standard size cupcakes. You can frost and sprinkle them too, if you like. They’ll look pretty served on the side!)
First thing, as usual, heat up your oven to 375°F (350°F for dark or nonstick pan). Line bottom of 15x10x1-inch pan with parchment paper and spray with baking spray with flour. Line six cavities of a muffin pan with paper liners. In large bowl, beat eggs with electric mixer on high speed about 6 minutes or until thick and lemon colored.
Add in 1/3 cup Betty Crocker Rainbox Mix Decors (aka sprinkles) and gently fold in with a rubber spatula. You could also mix them in with the mixer on the lowest speed.
Pour 3 1/2 cups batter into pan. Divide remaining batter among muffin cups.
Bake 14 to 16 minutes or until cake springs back when lightly touched in center and cupcakes test done when toothpick inserted in center comes out clean. Immediately turn cake upside down onto clean kitchen towel sprinkled with 1/4 cup powdered sugar; peel away the parchment paper.
While still hot, carefully roll up cake and towel from narrow end. Cool for 10 minutes at room temperature, and then about 1 hour in the refrigerator. Cool cupcakes 10 minutes. Remove from pan; cool completely, about 30 minutes and save for another use.
Unroll cake carefully, and remove towel.
Spread filling evenly over the cake’s surface. Allow the end to remain slightly curled.
Re-roll the filled cake, wrap in plastic wrap and refrigerate for 30 minutes.
Pour remaining cup of sprinkles into a large pan with sides. Using a spatula and one hand, lift the cake into the pan and place on top of the sprinkles. If you have food service gloves, this might be a good time to use them. This part can be a little messy.
Gently roll the cake back and forth until covered in the sprinkles.
Transfer cake to serving platter. Decorate with colorful picks and birthday candles. Store loosely covered in refrigerator. Let stand at room temperature 30 minutes before serving.