To make the graham cracker crust:

1. Preheat the oven to 350 degrees F. Line two standard 12-cup muffin tins with paper liners
2. In a small bowl, stir together the graham cracker crumbs, butter and sugar until well combined. Press a heaping tablespoon of the crust mixture into the bottom of each muffin cup and bake until golden and just set, 5 to 7 minutes. Set aside to cool

To make the cupcakes:

1. Whisk together cocoa and hot coffee until smooth
2. In another bowl, whisk together flour, baking soda and powder, and salt. Set aside
3. In a small saucepan, melt butter with sugar over medium-low heat, stirring to combine. Remove from the heat and pour into a mixing bowl. With a handheld or stand mixer, beat on medium-low speed until mixture is cool, approximately 4-5 minutes. Add eggs one at a time to butter sugar mixture, beating well after each addition. Scrape down sides of the bowl as needed to ensure ingredients are well incorporated. Add vanilla then cocoa mixture and beat until combined. Reduce speed to low and add flour mixture in two batches, alternating with the sour cream or yogurt, beating until just combined. Do not overmix
4. Using an ice cream scoop, place one scoop of batter in each lined muffin cup, filling each 3/4 full (note: you may have leftover batter). Bake until a toothpick inserted in center of cupcakes comes out clean, about 20 minutes, rotating pans after 10 minutes. Let cool in the muffin tins on a wire rack for about 5 minutes, then remove the cupcakes from the tins and allow to cool completely

To make the marshmallow frosting:

1. In mixing bowl with paddle attachment of a stand or handheld mixer, beat softened butter with powdered sugar on medium until fully incorporated. Beat in marshmallow fluff until light and fluffy then mix in vanilla
2. Scoop one heaping tablespoon of frosting and dollop on top of each cooled cupcake. It doesn’t need to be pretty – in fact, the messier the better in my opinion. With a kitchen torch, lightly brown the frosting, being very careful not to set the cupcake liners (or your kitchen) on fire. Top each cupcake with a piece of graham cracker and chocolate. Serve and enjoy!