1. Prepare the Macaron Shells

• Preheat the oven to 300°F (150°C). Line two jelly roll sheets with parchment paper or a Silpat baking mat. Set up two piping bags with a 1/2 inch round tip.
• Prepare the egg whites: Separate the egg whites from the yolks. Be sure that no yolk gets into the whites. Measure out 100 grams of egg whites (roughly three eggs), cover them with plastic wrap, and let them stand at room temperature overnight. Alternatively, if you’re short on time, microwave the egg whites for 20 seconds, in 5-second intervals, mixing after each stop to slightly warm them up.
• Prepare the dry ingredients: In a food processor, combine the 200 grams powdered sugar, 50 grams almond flour, and 50 grams shelled pistachios. Pulse for about 20 seconds, then process for another 3–4 minutes until you get a very fine mixture. Be sure to stop a few times to scrape the sides of the processor. Set the dry mixture aside.

2. Make the Meringue

• Whip the egg whites: In a clean bowl, start whipping the egg whites with a pinch of salt until they become foamy. Gradually add the 50 grams granulated sugar, whipping until stiff peaks form. This process may take about 5–7 minutes. If you’re using food coloring, add it here and mix it in until it’s evenly incorporated.

3. Combine Meringue and Dry Ingredients

• Incorporate the dry ingredients: Add half of the powdered sugar-pistachio mixture into the meringue and use a spoon to gently mix it in with quick swirling motions. Make about 5–6 swirls to ensure it’s incorporated. Then, add the remaining half of the dry ingredients and carefully fold them in with a spatula. Be gentle — overmixing will cause the batter to become too runny. Stop when the batter falls in a thick ribbon from the spatula and disappears into the bowl in about 30 seconds. This is a crucial step: the batter should be smooth but not runny. If you’re able to draw an “8” with the batter as it falls from the spatula, you’re good to go.

4. Pipe the Macarons

• Prepare to pipe: Transfer the batter into your piping bag. Hold the piping bag perpendicular to the baking sheet, and pipe out 1-inch circles spaced about 1.5 inches apart. The batter should settle naturally into a smooth, round shape.
• Sprinkle with pistachios: Gently sprinkle the chopped pistachios over the tops of the piped macaron shells.

5. Bake the Macarons

• Bake the first sheet: Slide the first sheet into the oven and bake for 10–12 minutes. You’ll know the macarons are ready when the tops are dry to the touch, and they lift cleanly off the parchment paper. Be careful not to overbake as they can dry out quickly.
• Cool and remove: Once baked, allow the macarons to cool on the baking sheet. If you’re baking a second batch, ensure the baking sheet has cooled down or use a new sheet. The second batch should also bake for 10–12 minutes.

6. Make the Pistachio French Buttercream

• Make the sugar syrup: In a small saucepan, combine 6 tablespoons of granulated sugar and 2 tablespoons of water. Bring the mixture to a soft ball stage. To check, drop a small amount of syrup into a glass of cold water. When it forms a soft ball, remove the pan from the heat.
• Whip the butter and egg: In a stand mixer, whip 100 grams room-temperature butter for about 3 minutes until it’s light and fluffy. In another bowl, whip the egg to soft peaks. Gradually pour in the warm sugar syrup while the mixer is running. Continue whipping until the mixture is cool to the touch.
• Combine butter and syrup: With the mixer still running, slowly add the whipped butter to the egg mixture, one tablespoon at a time. After adding all the butter, the mixture might look runny or curdled. Keep whipping until it becomes smooth and creamy. If you want, fold in 50 grams of finely chopped pistachios.

7. Assemble the Macarons

• Pair the macaron shells: Once the shells are completely cool, match up pairs of similar-sized shells.
• Fill the macarons: Using a pastry bag (or a ziplock bag), pipe a generous amount of pistachio buttercream onto one macaron shell and sandwich it with its pair. Press gently to spread the filling evenly.
• Let the macarons mature: Store the filled macarons in a tightly sealed container. Let them rest for 24–48 hours at room temperature or in the fridge to allow the flavors to meld. When ready to serve, bring them to room temperature for the perfect texture.