These tasty Muddy Buddy Bars are a fun twist on the classic snack mix. Crunchy cereal is surrounded by sweet marshmallows, chocolate, and peanut butter.
Line a 9x9-inch pan with parchment paper, leaving a 1-inch overhang on either side.
Add 6 cups rice Chex cereal to a large bowl.
Add 1 ½ cups semi-sweet chocolate chips, ⅔ cup peanut butter, and 6 tablespoons salted butter to a medium microwave-safe bowl. Heat in the microwave in 30-second increments, stirring between each increment, until everything is smooth and completely melted.
Stir in 4 cups mini marshmallows and heat for another 45-60 seconds. Stir until the marshmallows are fully melted.
Stir in 1 teaspoon vanilla extract before pouring the chocolate mixture over the cereal. Stir until the cereal is evenly coated.
Transfer the cereal mixture to the prepared pan and even it out as much as you can. Let the bars chill in the refrigerator for at least an hour, until the bars are firm.
Before serving, remove the bars from the pan, dust liberally with ⅓ cup powdered sugar, and slice into bars.