In a large microwave-safe bowl, combine Honey Nut Chex, Wheat Chex, pretzels, peanuts, and stir to mix well. Set aside.

In a 2-cup glass measuring cup or medium microwave-safe bowl, add butter and microwave on high for about 30 seconds until melted.

Add brown sugar, corn syrup, pumpkin pie spice, and salt; stir until well combined.

Microwave the mixture until bubbly and boiling, about 30 seconds, watching closely.

Drizzle the hot sugar mixture evenly over the cereal mixture and stir to coat evenly.

Microwave the coated mixture on high for 3 minutes, stirring every minute.

Allow the snack mix to cool for about 5 minutes. Then add dried cranberries and candy corn, stirring to combine. Serve immediately.