In a heavy bottomed saucepan over medium heat add the condensed milk, butter, Cocoa Pebbles, and cocoa powder. Stir with a wooden spoon until all the ingredients are mixed together
When mixture begins to a boil, lower the heat and stir for 4-5 minutes more or until it becomes thick and creamy being careful not to burn the bottom
Remove from heat and add the mixture into a bowl previously greased with cooking spray or butter. Let the mixture cool in the fridge for at least one hour
When the mixture is cool, roll into balls, about the size of a teaspoon and place on a sheet with parchment paper
Pour Cocoa Pebbles in one bowl and the Fruity Pebbles in another bowl
Dip each ball into the either cereal and move it around until all the fudge ball is completely coated
Balls can be served at room temperature. Refrigerate leftovers