• In a medium bowl, add the almond flour, arrowroot starch, cocoa powder, espresso powder, baking soda, and salt. Whisk well to combine until there are no clumps and the cocoa powder is evenly distributed. Set aside.
• In a large bowl, add the egg and egg yolk, coconut sugar, and avocado oil. Whisk for at least 30 seconds, until the mixture is very smooth and totally incorporated, resembling a caramel sauce. Add the vanilla and whisk again until smooth.
• Add the dry ingredients to the wet, incorporating using a wooden spoon. Mix until totally combined and there are no streaks of flour. Stir in the chocolate chips, then fold in ½ cup mini marshmallows, making sure they’re evenly dispersed throughout the dough.
• Cover the bowl with cling wrap and transfer to the fridge. Chill for 30 minutes.
• Meanwhile, preheat the oven to 350°F. Line two baking sheets with parchment and set aside.

To Finish & To Store:

• Remove the dough from the fridge. Using a 2-tablespoon cookie scoop, portion the dough into 18 cookies. Roll into balls and place 9 cookies on each sheet, leaving 2 inches of space between them. Gently press down with your fingers to flatten slightly and top with flaky salt.
• Transfer to the oven and bake for 4 minutes.
• Remove the trays from the oven and press 2–3 additional mini marshmallows into the top of each cookie, pressing them securely into the warm dough.
• Return to the oven, rotating trays top to bottom. Bake for an additional 5–6 minutes, until the edges are set and the marshmallows are puffed and lightly golden.
• Transfer to a wire rack and cool completely before storing in an airtight container. They’ll keep for 3 days at room temperature. Enjoy!