Measure 9 cups Rice Chex into a very large bowl and set aside.

In a microwave-safe bowl, combine 1 cup milk chocolate chips and 1/2 cup creamy peanut butter. Microwave on high in 30-second intervals, stirring between each, until smooth and fully melted.

Stir 1 teaspoon vanilla extract into the melted mixture.

Pour the chocolate-peanut butter mixture over the Rice Chex. Gently fold with a spatula until the cereal pieces are evenly coated.

Add 1/2 cup powdered sugar and 1/2 cup crushed Andes mints to a large resealable bag.

Transfer the coated cereal into that bag, seal, and shake until the pieces are evenly dusted.

Spread the finished Muddy Buddies onto a parchment-lined baking sheet in an even layer to cool and set.

Garnish with extra Andes mints (halved or whole) while the mix is still slightly tacky for best adhesion.

Let cool completely, then enjoy.