Pre-heat oven to 350 degrees and lightly spray a whoopie pie pan with oil.
In a large bowl, whisk together flour, baking powder, salt, and sugar.
Add milk, melted butter, egg and vanilla to dry ingredients and whisk until smooth.
Fold in Sherbet Fruity Pebbles
Fill cavities of whoopie pie pan halfway.
Bake 7-9 minutes at 350 degrees, until just beginning to turn golden around edges.
Immediately remove pancakes from whoopie pie pan and stack pancakes on plates.
Pour vanilla icing over pancake stacks and sprinkle with more Sherbet Fruity Pebbles