01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk together flour, baking soda, and salt in a medium bowl. Set aside.
03 - Beat softened butter, granulated sugar, and brown sugar with electric mixer until light and fluffy, about 2-3 minutes.
04 - Add eggs one at a time, beating well after each addition. Mix in peppermint extract, vanilla extract, and green food coloring until evenly colored.
05 - Gradually add dry ingredients to wet mixture, mixing on low speed just until combined.
06 - Fold in chocolate chips and chopped dark chocolate.
07 - Scoop tablespoon-sized portions onto prepared baking sheets, spacing about 2 inches apart.
08 - Bake for 9-11 minutes, until edges are set but centers remain soft.
09 - Cool on baking sheets for 5 minutes, then transfer to wire rack to cool completely.