Red white and blue sprinkles (again make sure the sprinkles you use are 100% vegan. I honestly have no idea which store bought sprinkles are safe and I ended up ordering some online)
Prepare the cake batter as directed on the box. Once mixed separate the batter into two separate bowls trying to get equal amounts of the batter into each bowl.
In one bowl add the red food coloring and in the second bowl add the blue. Each brand of food coloring seems to vary as far as coloring so use the amount of food coloring you feel necessary to achieve the desired shades of red and blue.
Once both batters are colored line the cupcake pan with the cupcake liners and fill with the two cake batters (make solid color cakes do not mix the colors) and bake as directed on the package. (Try to bake equal parts of both red and blue cupcakes.)
Once the cupcakes are done baking set on the counter and allow to cool completely.
Once cool remove the cupcakes from the pan and remove the cup cake liner. Slice each cupcake in half (so you have a top and a bottom). Do this for the all of the remaining cupcakes.
In a jar add one of the cupcake bottoms to the jar (you can do all red, all blue or alternate between the two colors) add some of the frosting and then add the top of the cupcake. Top it off with more frosting and sprinkles. Repeat this method for all of the remaining.