Line a cookie sheet with a silicone mat or you can use parchment paper if you don’t have one.
Sift together the powdered sugar and almond flour.
In a medium bowl, prepare the french meringue. Beat the egg whites on low speed with a hand mixer until they get frothy. Increase the speed and slowly add the sugar. Beat until stiff peaks form. Add one drop of red food coloring, if desired.
Add the french meringue into the dry ingredients and begin to gently fold. The batter should be fully combined and not streaky. When you are able to make a figure 8 with the batter in one motion, the batter is ready. If it is too runny it has been over-mixed.
Transfer the batter to a piping bag fitted with a piping tip. Pipe 2-inch disks on to the silicone mat. The macarons will spread before baking.
Tap the cookie sheet on the countertop 3 or 4 times to get rid of any air bubbles. Use a toothpick to pop any remaining air bubbles.
Allow the macarons to rest for an hour or until the tops of the macarons have dried. You will be able to gently run your finger over them without anything getting on your finger.
Preheat the oven to 280 degrees (F).
Place the macarons on the middle rack of the oven and bake for 7 minutes, rotate the cookie sheet and bake for another 7 minutes, rotate the pan one last time and bake for 5 minutes. 19 minutes in total.
Remove from the oven and allow to cool completely on the cookie sheet.
If the macarons were baked correctly they should easily peel off of the silicone mat.