Green Mint Chocolate Chip Cookies

In a large bowl or stand mixer, beat the butter and sugar together for 1 minute. Scrape the sides and bottom of the bowl, then beat on medium for about 1-2 minutes, or until light and fluffy.
1 Cup Butter, 1 ½ Cups Sugar
Add the eggs + yolk, peppermint extract, and food coloring, beating together just until smooth.
2 Large Eggs, 1 teaspooon Peppermint Extract, 10 Drops Green Food Coloring
In a separate bowl, combine flour, baking powder, baking soda, cream of tartar, cornstarch and salt. Dump into the wet ingredients and combine until the flour is almost mixed in.
3 ¼ Cups Flour, 2 teaspoons Baking Powder, 1 teaspoons Baking Soda, 1 ½ teaspoons Cream of Tartar, 1 teaspoon Cornstarch, 1/2 teaspoon Salt
Add half of the chocolate chips to the dough.* Chop the other half coarsely, with a knife to add the small flecks like you see in mint chocolate chip ice cream.
12 Ounces Dark Chocolate Bars, chopped
Add the chopped chocolate to the dough, and mix until just combined.
Cover the dough and refrigerate for about 1-2 hours.
Preheat the oven to 350 degrees F. Line one or more baking sheets with parchment paper or a silpat.
Use a 1/4 cup measuring cup to form balls of dough. Place them on the cookie sheet lined with parchment paper.
Bake at 350 for about 8-10 minutes, or until BARELY starting to brown on the edges. Do not brown the tops.
Let cool 5 minutes on the pan, then remove to a cooling rack.