Preheat your oven to 350°F (177°C) and line your baking sheets with parchment paper.

In a large mixing bowl, cream together unsalted butter, light brown sugar, and corn syrup until light and fluffy.

Add egg and vanilla extract, and mix until well incorporated.

In a separate bowl, whisk together all-purpose flour, baking soda, fine sea salt, and instant espresso powder.

Gradually add dry ingredients to the creamed mixture, stirring until just combined, then fold in mini chocolate chips.

Roll dough into 1-inch balls, coat in cocoa powder, and place on lined baking sheets.

Bake for about 10 minutes until puffed and golden. Allow to cool for a few minutes before dusting with powdered sugar.