Preheat oven to 325 degrees.
Prepare a pipping bag with a round tip with about a 1/4" opening (Ateco #804 is what I use) and a baking sheet lined with parchment paper.
In a medium bowl, sift almond flour and powdered sugar together. Set aside.
In a stand mixer with a whisk attachment, beat egg whites on high speed until they form soft peaks.
Lower the mixer's speed to medium and add sugar.
Put mixer back on the highest speed and beat until they form stiff peaks.
With the mixer still on high speed, add food coloring a few drops at a time until you get desired color.
Take bowl off of mixer and add almond flour/sugar mixture.
Using a rubber spatula, aggressively fold in dry ingredients until the batter starts to loosen and becomes a little runny. To test if the batter is ready, lift a small amount of batter from the bowl and drop it back into the batter. If it does nothing, keep mixing. If it slowly melts back into the batter after 20-30 seconds, it is ready.
Put batter (about 1/3 of the mixture) into prepared pipping bag and cover the rest of the batter with saran wrap
Pipe 1 1/2" circles on prepared baking sheet and firmly tap the bottom of the tray so the batter flattens out. Repeat with remaining batter.
Let them rest for 30-45 minutes until they form a skin.
Bake for 10-12 minutes, or until they are set.
Let cool before peeling them off parchment paper.
