Start with a clean dry mixing bowl.
Preheat oven to 225°.
Place a large piece of parchment paper onto a large cookie sheet.
Pour egg whites and sugar into a mixing bowl and stir until combined.
Add cream of tartat and flavored extract.
Mix on high speed until soft peaks form (about 5-8 minutes).
Divide meringue mix into three small bowls.
Add a few drops of food coloring to each dish and stir until you have the desired color.
Transfer each color meringue to a piping bag with different piping tips.
Work with one color at a time to pipe the monster shapes onto the parchment-paper-covered cookie sheets.
Store the other two piping bags with colored meringue in the refrigerator so they stay cold until needed.
Repeat the above step until all monster meringues are pipped onto the cookie sheet.
Bake for 30 minutes. Do not open the oven door while baking.
Keeping oven door closed, turn the oven temperature OFF and let the meringue sit in the oven while it cools down fo 1-1/2 hours. Do not open the oven door during this time.