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

In a medium bowl, whisk together the gluten-free all-purpose flour, unsweetened cocoa powder, baking soda, and salt.

In a separate large bowl, cream together the softened unsalted butter, brown sugar, and granulated sugar until light and fluffy, about 2-3 minutes. Add the eggs one at a time, mixing well after each addition, then stir in the vanilla extract.

Gradually add the dry ingredients to the wet mixture, mixing until just combined. Fold in the semi-sweet chocolate chips and mini marshmallows.

Scoop out portions of dough and roll them into balls, placing them on the prepared baking sheet about 2 inches apart.

Bake for 10-12 minutes until the edges are set but the centers still look soft. Let cool on the baking sheet for 5 minutes before transferring to a wire rack.