Preheat your oven to 350°F and line a baking sheet with parchment paper. In a small bowl, dissolve the instant espresso powder in 1 teaspoon of hot water and set aside.
In a large bowl, whisk together almond flour, granulated erythritol, baking powder, and salt until well combined.
Add the softened butter, egg, vanilla extract, and dissolved espresso to the dry ingredients. Mix with a spatula or hand mixer until a smooth, thick dough comes together.
Fold in the sugar-free dark chocolate chips until evenly distributed. The dough should be slightly soft but easy to scoop. If it feels too sticky, let it rest for 5 minutes. Scoop rounded tablespoons of dough onto the prepared baking sheet, spacing them about 2 inches apart. Gently press down on each cookie with your palm to flatten slightly.
Bake for 11-13 minutes until the edges are lightly golden and the centers look just barely set. Do not overbake, as they will continue cooking on the hot baking sheet.
Let the cookies cool on the baking sheet for at least 10 minutes before removing. They firm up as they cool, giving you a rich espresso flavor with pockets of melty dark chocolate in every bite.
