A cupcake sheet cake spares you the extra task of cutting a cake into individual portions, making serving the cake much easier. At first glance, a cupcake sheet cake appears to be a standard sheet cake because the top is decorated as a single unit, but the cupcakes pull apart separately. A standard full sheet cake measuring 16 by 24 inches rests on a 19-by-27-inch piece of cardboard, which holds about 48 regular cupcakes. There are smaller sizes -- a half-sheet and quarter-sheet -- that are decorated in the same way, though these are not technically sheet cakes.
Things You'll Need
- 19-by-27-inch cake cardboard
- Decorating bag
- Large round or flat decorating tip
- Icing spatula
- Small or medium round decorating tip
Lay a 19-by-27-inch cake cardboard piece on a flat work surface. If you're unable to find this size sold with cake decorating supplies, cut a piece of clean cardboard to this size and cover it in parchment paper.
Arrange unfrosted cupcakes in straight rows and columns on the cardboard, making sure the cupcakes touch each other. About 48 cupcakes fit on a full sheet board, but fewer might fit if you use large cupcakes or cupcakes with large domed tops. To best create the look of a flat sheet cake, fill the cupcake liners no more than two-thirds full to avoid making cupcakes with domed tops.
Cut the tip from a decorating bag and insert a large round or flat decorating tip. Fill the bag with your choice of buttercream frosting. You can skip the decorating tip altogether, if desired, and simply squeeze the frosting through the cut hole.
Position the bag over a cupcake on one side of the top row of cupcakes. Squeeze the bag with firm pressure to start a thick stream of frosting flowing from the tip. Drag the bag across the top row to apply a fairly thick bead of frosting to all the cupcakes. When you reach the last cupcake in the top row, drag the frosting down to the next row, applying frosting to the second row while constantly squeezing the bag. Continue this process, going from side to side, until each cupcake has a stream of frosting on top.
Squeeze a line of frosting between each row of cupcakes. The cupcakes are pushed closed together, so these lines of frosting should be cover the edges of cupcakes in adjoining rows.
Spread the frosting smooth with an icing spatula. Add more frosting where needed to fill in low spots, creating a perfectly smooth frosting top. If the frosting seems stiff and doesn't spread easily, dip the spatula in a cup of hot water to heat the metal blade. Wipe the blade dry and continue spreading the frosting. The warm blade heats the frosting slightly, making it easier to spread.
Write a message or apply other decorations on the frosted surface of the cupcake sheet cake. Decorate the top of the cupcakes just as you would decorate a standard sheet cake. To write a message such as "Happy Birthday," for example, use a small or medium round decorating tip with frosting in a second color. Control the movement of the bag with your wrists as you write the message.
Tips & Warnings
- When looking from above, the cupcake cake should look just like a regular cake, but the sides of the cupcakes should be left uncovered so you can easily pull the cupcakes apart without a big mess.
- Photo Credit Martin Poole/Photodisc/Getty Images