Happy 4th of July!
I made a box cake mix (white) and divided the mix into 3 bowls. I used food coloring to make one bowl red, one blue and left the last white. Pour into cupcake wrappers/tins and baked as directed. I let them cool and cut them in half layering them in the jars with buttercream frosting. Made the little decorations. These didn't last long. They were gone shortly after this. I was lucky to get a picture.