Cut parchment paper to fit your baking sheet or line with silicone mats. Set aside.
Place almond flour and powdered sugar in a food processor and pulse to grind as finely as possible.
Sift the almond flour, powdered sugar, and matcha powder into a bowl, discarding any large bits, and whisk to combine. Make a well in the center of the dry ingredients. Add the 82 grams of egg whites. Stir to completely combine the ingredients. It will be a thick paste. Cover with plastic wrap.
Place the 90 grams of egg whites for the Italian Meringue into the bowl of a standing mixer with a whisk attachment.
In a small saucepan, combine the granulated sugar and water and place over medium- high heat. DO NOT stir once the sugar begins to boil. Stir just to combine and leave it be after that.
When the sugar hits 203℉ begin to whip the egg whites in the stand mixer at medium speed to soft peaks. If the egg whites hit soft peaks before the syrup is ready, bump the speed to low.
Once the syrup hits 245℉, remove from the heat. Bump the mixer's speed down to medium- low and very slowly pour the syrup into the bowl, making sure not to hit the whisk. It's best to aim for the edge of the bowl.
Increase the speed to medium (4 on a KitchenAid) and whip for about 10 minutes, or until the whites hold thick, glossy peaks. You will not have stiff peaks, but when you flip the bowl upside down, the meringue shouldn't move.
Stir about ⅓ of the meringue into the flour mixture until well combined. You can be a bit rough with this first addition. Now gently fold in the remaining meringue until you reach "ribbon stage". You should be able to lift some batter and drizzle a figure 8 in the bowl before it sinks back into the mixture.
Transfer the mixture to a large pastry bag fitted with a round tip (#12). Holding the bag straight up, pipe circles onto your baking sheet by applying even pressure (don't try to draw a circle). If you are using a template, you want to fill the circles until just shy of the edge. They will spread a bit in the next step.
Firmly bang baking sheet on the counter several times to even the batter and loosen any air bubbles. Use a toothpick to pop any surface bubbles.
Let the macarons sit on the counter for 30 minutes to an hour to form a skin. When you touch the surface it should feel dry.
About 30 minutes before the macarons are ready to bake, preheat the oven to 275°F. Once the macarons are dry, bake one sheet at a time for 18 minutes, rotating the sheet every 6 minutes. The macarons are done when they release from the baking sheet easily. Keep an eye on them and adjust the baking temperature and time as needed.
Cool on the baking sheet for 10 minutes before transferring to a cooling rack to cool completely.