In the bowl of a stand mixer beat egg whites until fluffy and stiff peaks form.
Add sugar and beat again until stiff peaks form. You should be able to lift the beater out of the egg whites and a point forms that does not collapse.
Add chocolate chips and the mint extract right on top of the chips as well as the food coloring. It helps if the liquid does not hit the egg whites directly as it could start to collapse them.
Gently stir in the chocolate chips, mint, and food coloring until combined, being careful not to stir too hard as the egg whites are fragile.
Scoop up the mixture with a teaspoon and place on the prepared cookie sheets about 2 inch apart.
Once all the cookie sheets are full and all of the mixture is used up, place the cookie sheets into the oven. Close the oven door and wait three seconds. Turn the oven off and leave the meringues in the oven for at least 3 hours, or overnight. The foil will retain the heat and dry the merengues completely as they rest.
Notes
If you are like me and cook a lot I like to do this overnight so I don't need to use the oven. I also often put a sign on the oven door and/or the oven controls so that I don't accidently forget they are in there and turn on the oven. :-)