Do a little food prep.
Measure out the cereal and pout into a large bowl. Spread the dry brownie mix and powdered sugar on two separate cookie sheets. Alternatively, add the brownie mix and powdered sugar to two separate gallon-sized zip top bags (much easier clean up!).
Melt the chocolate.
In a microwave-safe bowl, combine the chocolate chips and peanut butter and heat in 30 second intervals, stirring well in between, until the mixture is completely melted and smooth. Drizzle the chocolate mixture over the cereal and gently stir with a spatula until the cereal is evenly coated.
Coat the cereal.
Divide the chocolate covered cereal in half, spooning one portion into the dry brownie mix and the second portion in the powdered sugar. Securely close the bags, if using. Gently toss the cereal in the coatings until evenly coated. Gently break apart clumps as needed. Let cool completely.
Combine the brownie and powdered sugar coated cereals in a large air tight container, add in the gluten-free pretzels and chocolate candies then serve. Store in an air tight container for 3-4 days at room temperature, if it lasts that long.
Adapted from Mel's Kitchen Cafe