Measure the 9 cups plain Chex cereal into a very large mixing bowl (bigger than you think you need). Set aside.
Over medium heat, melt and combine the 1 cup semi sweet chocolate chips, 1/2 cup smooth peanut butter and 1/4 cup butter, stirring constantly.
When fully melted, stir in the 1 teaspoon vanilla.
Pour the chocolate mixture over Chex cereal in 3 stages, folding as you go. Toss gently to coat all pieces.
Combine the 2 cups powdered sugar and crushed 1 cup peppermint candy in a large, airtight plastic bag, shake to combine.
While still tacky, add the covered Chex cereal in stages, tossing to cover and then removing to a parchment paper lined rimmed baking sheet.
Spread in a single layer and chill for an hour to set. Remove. Keep at room temperature or chilled.
If you've tried this recipe, come back and let us know how it was in the comments or star ratings.
Notes
Sometimes you can find the peppermint candy or candy canes already crushed. I put mine into a food processor and blend for a super fine mix. Alternatively, you can place it into a double bagged air tight plastic bag and mash with the flat side of a meat mallet or rolling pin.Storage: To keep puppy chow longer, store it in the fridge in an airtight container or resealable plastic bag for up to 2 weeks.Freezing: You can freeze puppy chow for up to 3 months but its texture may not remain the same after thawing. It does taste great eaten cold!