Line 2 large sheet pans with Silpat mats or parchment paper. Fit a piping bag with a small, round tip (I like a Wilton #10 or 12) and set aside.
Heat a small saucepan of water over medium-low heat. Place a heatproof bowl over the pot, making sure it doesn’t touch the water.
Add the egg whites and granulated sugar to the bowl. Whisk them together continuously until the sugar has fully dissolved, about 4-5 minutes.
3 large egg whites, ½ cup granulated sugar
Transfer the egg whites and sugar to the bowl of a stand mixer fitted with the whisk attachment. Beat the egg whites on medium-high speed (Kitchenaid #6-8) until they form a stiff peak.
Sift the powdered sugar and almond flour through a fine-mesh sieve into the egg whites. Fold in the powdered sugar and almond flour gently, making sure not to deflate the egg whites yet. Make sure to scrape all the way to the bottom of the bowl while you fold.
⅘ cup powdered sugar, 1 cup almond flour
Smush the batter against the sides of the bowl and fold it back together until the meringue flows smoothly. When the meringue is ready to pipe, you should be able to draw a figure 8 without the stream breaking.
Transfer the meringue to the piping bag fitted with the round tip. Pipe 1-inch macarons about 2 inches apart on the Silpat-lined baking sheet.
Immediately when you’ve finished piping a tray, hold the tray 6 inches off the counter and drop it straight down to release any air bubbles. Repeat 5-6 times, or until it appears that any large air bubbles have popped.
Allow the macarons to sit at room temperature until they have formed a skin, about 30 minutes. While the macarons rest, preheat your oven to 325°F.
Bake the macarons one tray at a time for 14 minutes, turning the tray half way through cooking. Repeat with the second tray.
Allow the macarons to cool fully before removing them from the tray.