Chocolate and peppermint are a winning combination when it comes to desserts. These cookies have deep, rich chocolate flavor from cocoa powder and semisweet chocolate, as well as cool peppermint flavor from peppermint extract.
Preheat the oven to 350 degrees.
Mix together the flour, cocoa powder, baking soda, and salt in a medium bowl and set aside. Beat the butter and sugars in large bowl with an electric mixer on medium speed until light and fluffy. Add the eggs and the extract and mix well. Gradually beat in the flour mixture on low speed until well mixed and stir in the chocolate.
Drop by rounded tablespoons about 2 inches apart onto baking sheets sprayed with nonstick cooking spray.
Bake for 8 to 10 minutes or just until cookies are set. Cool on baking sheets for 2 minutes. Remove to wire racks and cool completely.