01 - Preheat oven to 350°F and line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together flour, baking soda, and salt; set aside.
03 - Using an electric mixer or sturdy whisk, beat softened butter with granulated and brown sugars until light and creamy, about 2 minutes.
04 - Add egg, vanilla extract, and peppermint extract to the creamed mixture; blend until fully combined.
05 - Gradually add the dry ingredients into the wet mixture, stirring until just combined without overmixing.
06 - Fold in semi-sweet chocolate chips and crushed peppermint candies evenly.
07 - Scoop tablespoon-sized dough balls onto prepared baking sheets, spacing them 2 inches apart.
08 - Bake in preheated oven for 10 to 12 minutes, until edges are set and centers appear slightly underbaked.
09 - Let cookies cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.