Begin by breaking high-quality white chocolate into small pieces and placing them in a microwave-safe bowl. Microwave the chocolate in 30-second intervals, stirring in between, until the chocolate is glossy and smooth—this should take about 1 to 2 minutes.

In a large mixing bowl, combine Rice Chex cereal, pretzels, salted cashews, and M&M’s. Gently fold them together with a spatula, ensuring an even mix.

Once the white chocolate is melted, drizzle it generously over the dry mixture in the bowl. Gently fold the ingredients together with a spatula, being careful to coat everything evenly.

Spread the coated mix onto a large sheet of wax paper or a parchment-lined baking tray. Use a spatula to make an even layer and refrigerate for about 30 minutes.

After chilling, break the mixture into bite-sized clusters with your hands.