Add the egg whites to the mixture. Whisk until the batter is smooth and no pockets of powdered sugar remain. It will become thick and sticky. If it’s a little runny, add 1 to 2 tablespoons of cocoa powder. Cover it with plastic wrap and place it in the freezer for 10 minutes.
Step 4:
Line a large cookie sheet with a sheet of parchment paper or a silicone mat.
Step 5:
Drop a tablespoon of the cookie dough onto the baking sheet. Repeat with the remaining dough, spacing them 2 inches apart.
Step 6:
Place inside the oven and bake at 320F for about 15 to 18 minutes. Once done baking, let them cool and set completely on the cookie sheet. Serve and enjoy!