- 1 2/3 cups flour
- 1 tsp cornstarch
- 1 tsp baking soda
- 1/2 tsp salt
- 1/2 cup unsalted butter, at room temperature
- 1/2 cup sugar
- 1/4 cup light brown sugar
- 1 large egg
- 1 tsp vanilla extract
- 1/4 tsp pure peppermint extract
- 1 cup white chocolate peppermint chunks
- 4 ounces white chocolate, chopped
- Whisk together flour, cornstarch, baking soda, and salt in a medium bowl. Beat butter and sugars in a large mixer bowl at medium speed until creamy; beat in egg and extracts until combined. Reduce speed to low and gradually add flour mixture; beat just until incorporated. Fold in white chocolate peppermint chunks. Cover dough and chill in the refrigerator for at least 4 hours or overnight.
- Preheat oven to 350°F (If cookie dough has chilled overnight, let stand at room temperature for 30 minutes before baking). Line two baking sheets with silicone mats or parchment paper. Form 1 1/2-inch balls of dough and place two inches apart on prepared baking sheets; flatten mounds slightly. Bake, rotating pans halfway through, for 11 to 12 minutes, until tops and edges are set. Cool for 5 minutes on baking sheets, then transfer to a wire rack to cool completely.
- Place white chocolate in a double boiler or in a heat-proof bowl over a saucepan of gently simmering water. Slowly melt the chocolate, stirring occasionally until glossy and smooth. Transfer chocolate to a small piping bag and drizzle over cookies. Top with sprinkles and let chocolate set before serving. Store at room temperature in an airtight container.