Preheat oven to 325 F. Sift together the almond flour and powdered sugar to remove any lumps.
Whip the egg whites until frothy. Add the granulated sugar and powdered egg whites. Whip until stiff.
Add a few drops of food coloring to the egg whites mixture according to the flavor being made (raspberry = light pink, pistachio = light green, lemon = light yellow, etc.).
Gently fold one third of the almond mixture into the whipped egg whites. The mixture should stay streaky. Lightly fold in another third of the almond mixture. Fold in the remaining almond mixture, leaving a few specks of the egg whites visible.
Fill a pastry bag fitted with a 1/4-inch plain tip with the mixture.
Pipe the batter into rows of 1-inch kisses, 1/2 inch apart, onto parchment or silicone-lined baking sheets.
Bake for 11 to 14 minutes, rotating the baking sheet halfway through baking. 8. Allow the macarons to cool completely.
Assembly: Pistachio, lemon, or raspberry filling (recipes follow), or chocolate ganache
Pipe a 1/8-inch layer of filling onto the flat sides of half of the macarons.
Sandwich another unfilled macaron on top of the filling, pressing gently so it adheres. Refrigerate in an airtight container for up to 3 days.