• Adjust the oven rack to the middle position and preheat the oven to 350°F. Line 2 baking sheets with parchment paper or silicone mats; set aside. In a small bowl, whisk together the flour, baking powder, baking soda, and salt; set aside.

For the Coating

• Place the graham cracker crumbs in a small bowl. Add 1 tablespoon of melted butter and stir until the mixture resembles wet sand; set aside.

For the Cookie Dough

• In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter, sugars, and ¾ cup of graham cracker crumbs on medium-high speed until light and fluffy, about 2-3 minutes. Scrape down the sides of the bowl and add the egg and vanilla; beat on medium-low speed until incorporated. Reduce the speed to low and slowly add the flour mixture until combined.
• Using a #60 (½-ounce) ice cream scoop or a spoon, measure out 1 tablespoon of dough at a time and roll it into 1¼-inch balls. Gently roll the balls into the graham cracker crumb mixture and space them evenly onto the prepared baking sheets (12 per sheet). Bake one sheet at a time until the cookies are beginning to crack, about 10-12 minutes. Let the cookies cool on the sheet for 5 minutes.
• Meanwhile, adjust the oven rack 10 inches from the broiler element and heat the broiler. Place 1 marshmallow half, cut side down, in the center of each cookie. Broil cookies until marshmallows are deep golden brown, about 30 seconds, rotating the pan halfway through for even browning. Transfer the sheet to a wire rack and immediately place a Hershey Kiss in the center of the marshmallow, pressing gently. Repeat with the remaining cookies, marshmallows, and Kisses. Allow the cookies to cool for 30 minutes. Serve slightly warm or cool completely before storing in an airtight container. Enjoy!