Stir cereal squares, pretzel sticks, peanuts, and milk chocolate pieces together in a large bowl.
Melt the vanilla baking chips in a microwave-safe glass or ceramic bowl in 30-second intervals, stirring after each melting, for 1 to 3 minutes (depending on your microwave). Drizzle melted chips over cereal mixture. Pour mixture out onto a large piece of aluminum foil and cool for 30 minutes. Break into bite-size pieces.
