Line a 9”x13” baking dish with wax or parchment paper. Spritz with nonstick cooking spray. Set aside.

Chop the multi-colored Peeps into bite-sized pieces. Set aside.

Pour the crispy rice cereal into the large bowl, and set aside.

In a very large, microwave-safe bowl, melt the butter in the microwave for 30-seconds, covered.

Once the butter has melted, add the whole Peeps.

Melt in 45-second increments until the Peeps have melted completely. They will expand in the microwave as they melt, so keep an eye on them. (Mine took around 1.5 minutes-2 minutes.)

Stir vigorously, then add the vanilla extract, and stir a little more.

Pour the cereal into the marshmallow mixture, and stir quickly until the cereal is coated.

Add the chopped Peeps, and stir until mixed in.

Pour the cereal bar mixture to the prepared baking pan and gently spread the mixture into an even layer with a rubber spatula. (If the mixture begins sticking, spritz the spatula with the nonstick cooking spray.) Do not press down hard on the mixture, as your treats will be more compact.

Let the treats cool completely, about 20-30 minutes.

Cut into squares with a sharp knife, and enjoy within 2-3 days.