Prepare the strawberries: Place the freeze-dried strawberries in a food processor or zip-top bag and crush them into a fine powder. Some small pieces are fine for texture. Set aside about ½ cup of the powder for mixing with powdered sugar later.

Melt the white chocolate: In a microwave-safe bowl, combine white chocolate chips and butter (if using). Microwave in 20-30 second intervals, stirring between each, until fully melted and smooth. Stir in vanilla extract if desired.

Coat the cereal: Place the Rice Chex cereal in a large bowl. Pour the melted white chocolate over the cereal and gently fold with a spatula until evenly coated. Be careful not to break the cereal pieces.

Add strawberry flavor: Sprinkle the strawberry powder over the coated cereal and fold again until well distributed. The mix will start turning pink!

Sugar coat: In a large zip-top bag or another large bowl, combine powdered sugar with the reserved strawberry powder. Add the coated cereal mixture, seal the bag (or cover the bowl), and shake vigorously until everything is evenly coated in the sweet pink dust.

Cool and add extras: Spread the puppy chow on a parchment-lined baking sheet to cool for 10-15 minutes. Once set, mix in any optional add-ins like candies or marshmallows.

Serve or store: Transfer to an airtight container. Enjoy immediately or store for up to 1 week at room temperature.