Step 1: 1. Sift the almond flour* and powdered sugar into a bowl
Step 2: 2. Using an electric mixer**, whip the egg whites and gradually add in the granulated sugar until stiff peaks form. (Add gel food coloring if using. Make the color more vibrant than you want, because the color fades during baking.)
Step 3: 3. Fold in the almond flour and powdered sugar mixture into the egg whites in two portions. Be very careful! Over mixing or under mixing can lead to a puffy or flat macaron. Only fold until you cannot see many lumps or pieces of ground almond, and until the mixture resembles lava.
Step 4: 4. Pipe the mixture into circles about 1 1/2 inch in diameter onto a cookie sheet lined with parchment paper. Try and make them uniform and about the same size and shape.
Step 5: 5. Bang the tray onto the counter to release all air bubbles.
Step 6: 6. Wait for about 30 min until when you touch the cookie, it does not stick to your finger and has formed a sort of skin.
Step 7: 7. Bake at 300 degrees Fahrenheit (around 150 degrees Celsius) for around 25 min.
Step 8: 8. Let cool for about 5 min, and take one cookie, pipe whichever filling*** you are using and put another cookie on top.
Step 9: 9. You are finished!
Step 10: *If you cannot get almond flour, you can grind up some regular whole almonds with a food processor
Step 11: **If you do not have an electric mixer, you can whip them by hand with a whisk. Note: it will take longer.
Step 12: ***A filling could be a buttercream frosting or a chocolate ganache.