1-First, start with aging your egg whites: Separate 100 grams of egg whites from the yolks, seal them tightly, and refrigerate for 3-7 days. This step, which is sometimes debated among bakers, can help with texture but isn’t always essential more on that macaron myth later.

2-Next, for preparing the macaron shells, sift 150 grams of confectioner’s sugar and 125 grams of almond flour into a large bowl, discarding any unsifted particles to ensure a smooth mixture.

3-Then, whip the 100 grams of egg whites on medium speed until foamy, and gradually add 100 grams of granulated sugar in three additions, mixing briefly between each. Continue whipping until the mixture is glossy and forms medium peaks, which helps counter the myth that stiff peaks are always needed. Add ¼ teaspoon of green food coloring powder and mix until even, then fold half of the almond mixture into the egg whites with a spatula before adding the rest until the batter is smooth and glossy, flowing and recombining within 10-15 seconds.

4-Pipe the batter into rounds about 3.5 cm in diameter on parchment-lined baking sheets, spacing them about 4 cm apart. Tap the sheets to flatten the mounds and pop any large air bubbles if using, sprinkle coarsely ground pistachios on alternating rows. Let the shells rest at room temperature for 30 minutes while preheating the oven to 135°C (275°F) using convection if available, then bake for 15-18 minutes and cool on the pan before removing with an offset spatula.

5-Making the Pistachio Buttercream: For the filling, cream 75 grams of butter at room temperature with 75 grams of icing sugar on low speed. Add 50 grams of finely ground pistachios and beat on medium speed for 3 minutes, then mix in ½ teaspoon of vanilla extract and 1 tablespoon of whipping cream, beating for another minute. Finally, for assembly, pipe a dollop of the buttercream onto the macaron shells without pistachios and gently press a shell with pistachios on top. Refrigerate the assembled macarons for about 3 days to soften and enhance flavors.