In a large bowl, beat the butter, brown sugar, and granulated sugar until creamy, about 2 minutes. 2½ Tablespoons (35 g) unsalted butter 6 Tablespoons (75 g) packed light brown sugar 2 Tablespoons (25 g) granulated sugar
Add the egg and vanilla. Beat until smooth and fluffy. 1 large egg 1 teaspoon vanilla extract
Pour in the melted chocolate and mix until fully incorporated. 4 ounces (113 g) semi-sweet chocolate
Add the flour, cocoa powder, baking powder, and salt. Fold to combine. 6 Tablespoons (45 g) all-purpose flour 2 Tablespoons Dutch cocoa powder ½ teaspoon baking powder ¼ teaspoon salt
Fold in the chocolate chips. ¼ cup (43 g) semi-sweet chocolate chips
Using a large #20 cookie scoop scoop the dough (about 3 Tablespoons). and place onto a small parchment lined baking sheet. Cover and Chill for 15 minutes.
Dip each graham cracker in the melted butter on both sides letting extra butter drip off. Arrange graham cracker squares on the baking sheet spaced a few inches apart.2 Tablespoons (28 g) unsalted butter 6 graham cracker squares
Flatten each cookie dough slightly in your hands. Place a large marshmallow in the center and fold the dough around the marshmallow. Some of the marshmallow may be peeking through. You want most covered. Place on top of each graham cracker. I like to have the marshmallow that is peeking through on top so it gets a bit toasted when baking. I like to chill again for another 15 minutes to help with spreading. 6 large marshmallows
Preheat oven to 350°F (180°C). Line a baking sheet with parchment paper.
Bake for 10-12 minutes, until the edges are set and the tops are crackly. The centers will still look soft. Remove the cookie sheet from the oven. Take a large round cookie cutter and place around each cookie and swirl to shape into perfect rounds. Place a chocolate square on top of each cookie and press down slightly to flatten the cookie. 6 Hershey squares