Rainbow Cupcakes & Marshmallow Frosting

I've seen these rainbow cupcakes a thousand times on Pinterest so I finally decided to try them. Super easy and a blast for the kids!

First mix any light colored boxed cake mix according to directions.
We used Cherry Chip.

Divide your batter into a separate container for each color you'd like to use. In our case we decided on five colors and I had a last minute epiphany to use disposable cups for easier cleanup!
Once divided, (they don't have to be equal), add a different color food coloring to each cup.
I personally suggest using the gel coloring for a more vibrant color but we only had regular so that's what we used.

Only stir the batter enough to mix the color in. Try not to over stir.

Use a spoon to drop batter into paper lined cupcake pans. I varied the order of the colors so that they didn't all turn out the same.
When they're about 3/4 of the way full, you can use a toothpick to swirl the color a bit, or just leave it alone.

Bake them in the oven according to the box but take them out about 3-5 minutes early.
Leave the oven on.

Add a marshmallow to the top of each one. Make sure that it's stable(ish) and standing up. Carefully put back in the oven for three to five minutes.

When the time is up, and the marshmallows are soft. Remove from oven and squish each one down with a spoon.
I attempted to add sprinkles, (who doesn't love sprinkles?), but they didn't really stick.

That's all there is to it. These would also be good with regular frosting, or howabout frosting with swirly colors to match the cakes?