In a medium size microwave-safe bowl, add peanut butter chips, chocolate chips and shortening. Microwave on high for 1 minute, stir and continue to heat at 30 second intervals until completely melted and smooth.
In a large mixing bowl, combine Chex cereal and 3 cups of Golden Grahams. Pour peanut butter and chocolate mixture over the cereal and mix until well combined.
Pour cereal mixture into a large freezer bag and add powdered sugar. Shake until the cereal is completely coated.
Once cereal is coated, pour the bag onto a parchment paper lined cookie sheet. Gently add in remaining cup of Golden Grahams, marshmallows and Hershey chocolate bar pieces. Store in an airtight container.