In a large pan, melt butter, then stir in marshmallows until combined and melted together.
Add the box of cherry Jell-O and mix together.
Add Rice Krispies and mix well.
Place mixture in a 9x13 pan and pat down with a spoon. Adding a little butter to the back of your spoon will help the mixture from sticking to it.
Let cool. Once cool, melt chocolates according to package directions. Drizzle each color over Rice Krispies with a spoon or piping bag.
Immediately add the sprinkles.
Let dry, then ready to eat.