Prepare the Treats

1. Melt the Butter: In a large saucepan over low heat, melt the butter.
2. Add Marshmallows: Once the butter is melted, add the mini marshmallows and stir until completely melted and smooth.
3. Combine with Cereal: Remove from heat and immediately add the Rice Krispie cereal, stirring until the cereal is well coated.
4. Press into Pan: Grease a 9×13-inch baking dish and press the mixture evenly into the pan with a spatula.

Decorate the Treats

1. Cool: Allow the mixture to cool for about 10 minutes.
2. Cut and Decorate: Once cool, cut into squares or fun Halloween shapes using cookie cutters. Decorate with Halloween sprinkles, candy corn, or drizzle melted chocolate over the top.