Spray a glass casserole dish with cooking spray and set aside
In a microwave safe bowl add the first two ingredients, microwave 1 minute, stir, microwave 1 more minute, stir.
Stir in 4 C Rice Krispies and then the 4 C Fruity Pebbles. Pour mixture into prepared pan. Wet one hand with water, scrape the rest of the bowl with fingers, wet hand, press the mixture into the pan. Allow to cool for 20 minutes before cutting. (if you can wait that long!) Cover with saran to store.