Adjust oven rack to middle position and heat oven to 350 degrees. Line baking sheets with parchment paper. Whisk flour, baking powder, and salt together in a bowl.

Using a stand mixer, beat butter and sugar on medium speed until fluffy, 3-5 minutes. Add eggs, one at a time, and vanilla and peppermint extracts and beat until combined. Reduce speed to low, slowly add flour mixture, and beat until combined.

If dough is extra soft, refrigerate for 30-60 minutes until firmed up. Place about 1/2 cup extra sugar in a dish. Use a cookie scoop to make uniform size balls and roll them in the sugar and place 2 inches apart on prepared cookie sheets. Using a buttered and sugared bottom of a flat-bottomed drinking glass, flatten each ball just slightly (about 3/4-inch thickness) and sprinkle with with peppermint candies.

Bake until edges are set and beginning to barely brown but centers are still soft and puffy, 10-12 minutes. Let cookies cool on sheet for 10 minutes. Serve warm, or transfer to wire rack and cool completely. If desired, drizzle with a little chocolate.