Preheat oven to 350 degrees Fahrenheit. Line two baking sheets with Gefen Parchment Paper or Silpats.

Combine flour, cocoa powder, baking soda, and salt in a mixing bowl. Stir and set aside. Using an electric mixer, beat margarine until creamy, about three minutes. Add sugar and brown sugar, beating until light, about three minutes more. Add eggs one at a time, beating between each addition. Then add vanilla and peppermint extracts. Add dry ingredients and beat slowly until fully incorporated. Stir in both chips.

Place dough on baking sheets, about one rounded tablespoon of dough per cookie, about two inches apart. Flatten cookies a bit. Bake for 12 minutes, until cookies are lightly crisped on the edges and soft in the center. Remove from oven and cool for three minutes. Move to a wire rack to finish cooling completely. Store in airtight container.