Pour the confectioner's sugar, almond flour and graham cracker crumbs into a large food processor and blitz until well combined.
Using a fine mesh strainer, sift the mixture into a large bowl, then sift the mixture once again into another bowl. Set aside.
Pour the egg whites and sugar into a stand mixer fitted with a whisk attachment. Whisk the whites on medium until slightly frothy, about 2 minutes. Increase the speed slightly and whisk until the whites resemble a shampoo-like lather, about 2 minutes more. Increase the speed to the highest setting and whisk until stiff peaks form - about 2-3 minutes.
Sift 1/3 of the almond mixture into the egg whites and, using a rubber spatula, fold the mixture into the egg whites. Repeat until all of the almond mixture is integrated into the egg whites and the batter runs like lava.
Transfer the batter to a piping bag fitted with a round 1/2-inch tip. Pipe four dots on a baking sheet and place a piece of parchment paper over top. Repeat the step with another baking sheet and piece of parchment.
Pipe a little of the batter into a small bowl and dip a 1 1/2-inch round cookie cutter (I used a shot glass) into the batter. Press the cookie cutter into the parchment paper to make batter outlines. Be sure to make 24 per sheet.
Pipe the batter onto the baking sheets, using the outlines as a guide. Lift the baking sheets a little off of the counter and drop them. Rotate the sheets 90° and repeat the step. This will eliminate any air bubbles in your cookies.
Leave the piped macarons to air dry for 30 - 40 minutes. While the macarons are drying, preheat the oven to 325°F.
Once the macarons are no longer tacky to the touch, place them in the oven. Bake the macaron for 12-15 minutes. Let the macarons cool on the baking sheets for 10 minutes before transferring them to a cooling rack. Let cool completely.