Start out by spraying a 9x13 pan with cooking spray and set aside.

Next heat the butter in a large pot over medium heat. Once your butter is melted, toss in your marshmallows.

Allow the marshmallows to melt, and then remove from heat and stir in Chex cereal.

Pour your Chex into your 9x13 pan and press it down to become even.

Melt your white chocolate chips and microwave for 30-second intervals, stirring in between. Do this until chocolate is fully melted.

Then pour the chocolate into a piping bag and drizzle over the bars. Add sprinkles and allow to set up.

Slice and serve!