In a medium bowl, whisk together 2 cups of all-purpose flour, 1 teaspoon of baking powder, ½ teaspoon of salt, and 2 tablespoons of instant espresso powder until well blended.

In a large mixing bowl, beat together ¾ cup of unsalted butter, ½ cup of granulated sugar, and ¾ cup of brown sugar using an electric mixer on medium speed for about 2-3 minutes.

Add in 1 large egg and 1 teaspoon of pure vanilla extract. Beat until fully incorporated, scraping down the sides as needed.

Gradually incorporate the dry mixture into the wet ingredients, mixing just until combined.

Cover the bowl with plastic wrap and refrigerate the dough for at least 30 minutes.

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Scoop out 2-tablespoon-sized balls and place them about 2 inches apart on the prepared baking sheet.

Bake for 10-12 minutes, until edges are set but centers remain slightly soft.

Remove from oven and let cookies cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.

Whisk together 1 cup of powdered sugar, 1-2 tablespoons of milk or cream, and optional instant espresso powder for the glaze.

Once the cookies are cool, drizzle the espresso glaze over each cookie and allow to set for 15-20 minutes.