This cake was much simpler to make than I thought it would be. I followed a recipe from Glorious Treats, but just made a layer cake—the hidden flag seemed too difficult and time-consuming. Even just layering the different colored cakes gets the same overall effect. I just used two boxes of vanilla cake, made it according to the directions and separated it equally into three bowls. I added blue food coloring to one bowl, and red to the other—red took more food coloring than the blue. With the frosting, it's nice to fold in some whipped cream to make it thicker. It's also important to make sure the cake is fully cooled before you ice it (if it's still hot the icing will drip). I also put red and blue frosting on top, just to make it pretty.
2 boxes vanilla cake mix (and all the ingredients asked for on the box)
Red and blue food coloring
1. Prepare the cake mix as directed on the box.
2. Separate the unbaked cake mix equally into three bowls.
3. Add blue food coloring to one bowl and red food coloring to another.
4. Prepare a round cake pan by coating it with butter and flour. Cook the cake as directed on the box. If you have three round cake pans of the same size you can cook all three batches at once, otherwise, cook one cake, then take it out and wash the pan, cook the next cake, take it out and wash the pan and cook the last cake.
5. Prepare the frosting by folding some whipped cream into your vanilla frosting.
6. Assemble the cake by putting a thin layer of icing between each layer, and then frost the entire thing in whatever pattern you'd like.