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

In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Incorporate the eggs one at a time, followed by the vanilla extract, mixing well after each addition.

In a separate bowl, whisk together the all-purpose flour, baking powder, and salt. Gradually add this mixture to the wet ingredients until just combined.

Gently fold in the mascarpone cheese and cooled espresso until you achieve a uniform dough. If using, add in chocolate chips.

Using a cookie scoop or tablespoon, drop rounded balls of dough onto the prepared baking sheet, spacing them a few inches apart.

Bake in the preheated oven for about 12-15 minutes, or until the edges are set but the centers are still soft.

Once cooled, dust the tops with cocoa powder.