In a medium bowl, sift together the almond flour and powdered sugar, then set aside.
120 g almond flour, 200 g powdered sugar
In the bowl of a stand mixer fitted with the whisk attachment, or using an electric hand mixer, beat the egg whites on medium speed until nice and foamy.
120 g egg whites (approx. 4 large eggs)
Once you can your whisk begins leaving visible trails in the egg whites, gradually add the granulated sugar making sure each addition is fully incorporated before adding the next. Increase the speed to medium-high and beat until soft peaks form. Soft peaks = the egg whites falling back into themselves slightly when the whisk is pulled out.
90 g granulated sugar
Add pink gel food coloring, then beat on medium-high speed until stiff peaks form. Stiff peaks = your meringue should be clumping inside your whisk and your egg whites should stand up straight once the whisk is pulled out. (Be sure not to over-whip your egg whites otherwise you risk drying them out which will cause problems down the line).
Pink gel food coloring
Add sifted dry ingredients to meringue and fold (don’t stir) with a rubber spatula from the bottom of the bowl upward then press the flat side of your spatula through the middle (also known as macaronage). This technique when done properly will ensure that the air bubbles that you beat into your egg whites don’t all deflate when incorporated with the dry ingredients. You’re looking to beat out some of the air that was created in the whipping of the egg whites, but not so much that it’s fully deflated and prevents your macarons’ signature feet from developing. The batter will look very thick at first, but it will get thinner as you fold. Repeat the folding until the batter gets to a lava-like consistency (the figure 8 test is a great way to check your consistency; pick up the batter and let it flow down while drawing the figure “8”. If it can do that, immediately stop folding) This video is a great resource to see both how to macaronage and what your batter consistency should look like.
Transfer the batter into a pastry bag with a plain round tip.
Pipe out 1½-inch rounds about an inch apart on three baking sheets lined with parchment paper. (Feel free to print out a macaron template if you’re worried about size/uniformity).
Tap the baking sheets firmly on the counter a few times to get rid of any air bubbles. Then sprinkle the crushed Fruity Pebbles on the tops of each of the macarons. (If you don’t release the air bubbles, they will expand during baking and crack the tops of your beautiful macaron shells.)
10 g Fruity Pebbles
Let the macarons rest and dry for 30 minutes or until a skin has developed; on a humid day, it might take an hour or more. To see if it’s ready to be baked, lightly touch it. If the batter doesn’t stick to your finger, then it’s ready. (Don’t forget to remove the macaron templates, if using, before baking!)
While the macarons are resting, preheat the oven to 300˚F (150˚C) and position the oven rack in the center of the oven with an empty sheet pan preheating inside. (Place an oven thermometer inside the oven to ensure that the temperature is correct). Bake the macarons on top of the preheated sheet pan one tray at a time for 18-20 minutes, rotating the pan once halfway through the cooking process.
Allow macarons to cool. If the bottoms are a tiny bit sticky, keep them on the tray to cool off for about 10-15 min. If the bottoms are already brown, they peel off cleanly, or appear over-baked however, carefully take them off the tray immediately to cool down. It’s always better to over- rather than under-bake your macarons as the maturation process can typically salvage ones that are over-baked.
While macarons are drying and baking, prepare the Fruity Pebbles cereal milk frosting. Place ¼ cup (10 g) of the cereal and the milk in a small bowl. Leave to sit out at room temperature for 20-30 minutes, stirring occasionally, to allow the flavor of the cereal to infuse into the milk. Strain the mixture – you’ll need 2-3 tbsp (30-45 g). Top off with additional milk, if needed.
20 g Fruity Pebbles, 120 g milk
Place the remaining ¼ cup (10 g) of cereal in a small plastic bag, and crush until it’s a fine consistency.
20 g Fruity Pebbles
Beat the softened butter until smooth and creamy. Add the powdered sugar, crushed/powdered cereal, and 2 tbsp (30 g) of the cereal milk and beat until well combined. Add more powdered sugar if frosting is too thin or more milk if the mixture is too thick. Add salt if the frosting is too sweet (⅛ teaspoon).
60 g unsalted butter, 240 g powdered sugar
Transfer the cereal milk frosting into a pastry bag. Pair each macaron shell with another of a similar size and then fill the macarons, gently sandwiching them together.
Store the filled macarons in an airtight container in the fridge for up to 5 days and bring them back to room temperature before enjoying.