In a large zip close bag combine the lemon and lime gelatin powder with the powdered sugar. Shake to combine.
Melt the white chocolate candy melts in the microwave according to package instructions. Pour over the cereal and stir to coat. Add the chocolate coated cereal to the bag of powdered sugar (you may have to do this in batches), and shake until coated.
Spread out on a wax paper lined baking sheet or counter top to cool completely. Scatter the Golden Grahams all over the muddy buddies, and zest the lime on top if desired. Store in an airtight container. Enjoy!