Created by Mikekey on November 14, 2013
Step 1: Preheat oven to 375F. Place rack in middle position of oven.
Step 2: Line a 13-9 inch metal baking pan with 1 sheet of foil, allowing 2 inches of foil to hang over each end of pan. Butter foil, except for overhang.
Step 3: Whisk together flour, cocoa, soda and salt in a small bowl.
Step 4: Beat together butter and brown sugar in a large bowl with an electric mixer at high speed until pale and fluffy, about 3 minutes.
Step 5: Beat in egg until combined.
Step 6: Reduce speed to low and mix in flour mixture until just combined.
Step 7: Stir in chocolate chips and peppermint candy pieces.
Step 8: Spread dough evenly in pan and bake until puffed and beginning to pull away from sides of pan, about 20 minutes.
Step 9: Cool completely in pan, then, lifting with foil, transfer to a cutting board.
Step 10: Cut into bars and lift off foil with spatula.