For the Cookies

• Add the butter, brown sugar, and granulated sugar to the bowl of an electric mixer.
• Beat with the paddle attachment until the sugars and butter have combined and are light and fluffy, about 2 minutes at medium speed.
• Stir the egg, vanilla extract, and milk into the batter.
• Whisk the flour, cocoa powder, baking soda, and salt in a medium bowl or measuring cup. Once combined, stir into the butter mixture until your dough forms, making sure to scrape the sides for even mixing.
• Spoon the dough, 2 tablespoons at a time, and roll into rounds. Place on a lined baking tray,
• Freeze for 15 to 20 minutes.
• While the dough is chilling, preheat the oven to 350 degrees.

Make the chocolate filling:

For the Chocolate Filling

• Place the chocolate pieces into a glass bowl.
• Pour the cream into a saucepan and bring to a gentle simmer over medium heat.
• Pour over the chocolate. Allow it to sit for 5 minutes.
• Stir until the chocolate combines with the cream and no lumps remain.
• Set aside.

Baking and Assembly

• Place the chilled cookie dough balls onto a baking tray, keeping 2 to 3 inches apart.
• Bake for 10 minutes.
• Remove from the oven and immediately press the center of the cookie to create a well. I suggest using the back side of a shot glass or wooden spoon.
• Spoon 1 to 2 teaspoons of the chocolate filling into the cupped part of the cookie.
• Place 1/3 of a large marshmallow or 2-3 mini marshmallows on top of the chocolate.
• Return to the oven for 5 minutes.
• Remove from the pan and allow to cool on a cooling rack.
• You can use the leftover chocolate filling as a drizzle for a fun finish!