Graham Cracker Crust 

1. Preheat oven to 350F (175C). Fill two cupcake baking pans with 14 cupcake liners.
2. In a medium mixing bowl, add the graham cracker crumbs and granulated sugar. Mix ingredients to combine. 
3. Pour melted butter into bowl with graham cracker mixture and mix ingredients together with a fork until mixture resembles wet sand.
4. Spoon 2 tablespoons of the graham cracker mixture into each cupcake liner. Use the back of a spoon or fingertips to flatten graham cracker mixture into cupcake liners.
5. Bake graham cracker crust for 6-8 minutes. Graham cracker crust is ready when it takes on a light golden brown color.
6. Cool graham cracker crust as the chocolate cupcake batter is prepared. 

Chocolate Cupcake 

1. In medium mixing bowl, add the flour, cocoa powder, baking powder, baking soda and salt. Whisk ingredients together to combine.
2. In the bowl of stand mixer fitted with paddle attachment or with a hand-held electric mixer and a large mixing bowl, add the oil and sugar. Mix ingredients together at medium high speed. Next, mix in the sour cream to combine.
3. Beat the egg into wet batter at medium high speed until fully incorporated, about 30-60 seconds.
4. Reduce mixer speed to low. In an alternating fashion, starting and ending with the dry ingredients, mix half of the dry ingredients into wet batter followed by the coffee and vanilla extract and ending with the remaining dry ingredients.
5. Stop mixer and use a rubber spatula to scrape the sides and base of the bowl to catch any unmixed ingredients. Resume mixing chocolate cupcake batter at medium speed for an additional 30-60 seconds. The resulting batter should be slightly thick and smooth.
6. Equally scoop chocolate cupcake batter onto cooled graham cracker crust.
7. Bake chocolate cupcake batter for 16-18 minutes or until a toothpick inserted into the center of one of the cupcakes comes out clean.
8. Cool s’mores cupcakes in pan for 4-5 minutes before transferring to a cooling track to cool completely to room temperature. 

Swiss Meringue 

1. Thoroughly clean all kitchen tools (mixing bowl, whisk attachment of stand mixer and digital kitchen thermometer) that will be used for making the meringue ensuring there is no presence of residual grease.
2. In the bowl of a stand mixer, add the egg whites, sugar and salt. Whisk ingredients together to combine.
3. Cook egg white mixture over a double boiler/pot of simmering water while whisking consistently for 8-10 minutes or until the mixture registers 160 F (71C) on a digital kitchen thermometer and there is no presence of sugar granules in mixture. (In the absence of a digital kitchen thermometer, you can tell when egg whites are properly cooked by rubbing some of the mixture between your finger tips. If mixture is free of sugar granules, egg whites are ready to be whisked.)
4. Whisk warm egg white mixture at high speed until the base of mixing bowl is cool to touch and meringue has reached stiff peak stage, 8-10 minutes. Reduce speed to medium low and whisk in the vanilla extract into meringue. Stop mixer once vanilla extract has been fully incorporated into meringue.

Assembly 

1. Spoon swiss meringue into a large pastry bag fitted with your preferred pastry tip. I used a Wilton 1M pastry tip.
2. Pipe swiss meringue over cooled cupcakes in a swirl pattern.
3. Using a kitchen torch, toast the entire surface of swiss meringue piping on each cupcake until it takes on a rich golden brown color.
4. Sprinkle the tops of cupcakes with graham cracker crumbs (optional) and serve.