• Preheat oven to 350 degrees and lightly grease 6-cavity doughnut tin with cooking spray.
• In the bowl of a stand mixer or in a large bowl with a hand mixer, beat together butter and sugar until light and fluffy. Add the egg and vanilla extract and mix to combine.
• In a separate bowl, whisk together flour, baking powder, and salt.
• Pour dry ingredients into the butter/sugar, alternating with milk, and mix until just combined. Take care not to over-mix or doughnuts will be dense.
• Fold ½ cup Fruity Pebbles into the batter.
• Evenly distribute batter amongst cavities of prepared doughnut pan, filling tin almost all the way.
• Bake for 15 minutes, until the doughnuts are starting to turn golden and spring back when touched. Let cool in pan for a few minutes, before moving to wire rack to cool completely before icing.
• When doughnuts are cooled, dip upside down into icing to coat the tops. Sprinkle remaining cup of Fruity Pebbles over icing.

Vanilla Icing

• In a medium bowl, whisk confectioners' sugar, milk, and vanilla extract together. If you want your icing to be thicker, add more confectioners' sugar, 1 tablespoon at a time. If you want it to be thinner, add more milk, 1 teaspoon at a time.