1. Preheat the oven to 350F/177C and line 12 muffin tins with cupcake liners.

Chocolate Batter

1. In a medium bowl, whisk together the flour, cocoa powder, baking powder, salt and sugar using the Cuisinart EvolutionX Cordless Hand Mixer.
   80 grams all-purpose flour spooned and leveled, 20 grams dutch-process cocoa powder* spooned and leveled, 1 tsp baking powder, 1/4 tsp salt, 100 grams granulated sugar
2. Add the oil to the dry ingredients and whisk together until it's combined.
   60 mL canola oil
3. Add the egg and mix until it's fully combined and then add the milk and sour cream. Mix just until the cupcake batter is smooth. Set aside.
   1 large egg room temperature, 60 mL milk room temperature, 60 grams sour cream

Graham Cracker Batter

1. In a medium bowl, whisk together the flour, Graham cracker crumbs, baking powder, salt and sugar using the Cuisinart EvolutionX Cordless Hand Mixer.
   80 grams all-purpose flour spooned and leveled, 30 grams Graham cracker crumbs, 1 tsp baking powder, 1/4 tsp salt, 100 grams granulated sugar
2. Add the oil to the dry ingredients and whisk together until it's combined.
   60 mL canola oil
3. Add the egg and mix until it's fully combined and then add the milk and sour cream. Mix just until the cupcake batter is smooth.
   
   Alternate scooping spoonfuls of chocolate batter and Graham cracker batter into each muffin tin until they are all 2/3-3/4 full.
   1 large egg room temperature, 60 mL milk room temperature, 56 grams sour cream
4. Use a knife or toothpick to swirl the batters together and bake for 16-18 minutes. When you press on the center of the cupcake it should spring back.

Meringue Frosting/Marshmallow Frosting

1. Begin by thoroughly cleaning the aluminum bowl and the whisk attachment of the stand mixer (they can’t have any fat residue when making meringue). Once they’re clean and dry, place the egg whites and the granulated sugar in the bowl.
   4 large egg whites, 200 grams granulated sugar
2. In a small saucepan, bring 1/2 cup (118mL) of water to a simmer. Keep the water simmering on low heat and place the bowl with the egg whites and sugar on top of the saucepan, creating a double boiler. Whisk the egg whites and sugar over low heat for 5 to 10 minutes, until the sugar granules are dissolved. You can feel it between your fingers if the sugar is fully dissolved or you can use a candy thermometer and bring the mixture to about 150°F (65°C).
3. When the sugar granules are fully dissolved in the egg whites, remove the bowl from the heat and place it on the stand mixer fitted with the whisk attachment. Beat the mixture on medium-high speed, until stiff peaks form.
4. Add the vanilla extract and continue beating the mixture until it's no longer warm. This usually takes about 10-15 minutes. Remove half of the meringue into a separate bowl and set aside.
   1 tsp vanilla bean paste or extract

Chocolate Swiss Meringue Buttercream

1. Place half of the meringue back on the stand mixer and lower the speed to medium.
   1/2 of Meringue frosting
2. Slowly add in the softened butter, 2 to 3 tablespoons at a time. Once the butter is all incorporated, continue beating on medium speed for a few minutes until it emulsifies into a buttercream (it may go through phases of looking soupy and/or curdled before it emulsifies but it should come together within 5-10 minutes).
   172 grams unsalted butter room temperature
3. Once the buttercream comes together, add in the cocoa powder and the melted chocolate.
   20 grams cocoa powder spooned and leveled, 85 grams milk chocolate chips melted

Assemble

1. Once the cupcakes have cooled completely, use a knife or a cupcake corer to remove a hole in the center. Discard (or eat) the removed part.
2. Use a piping bag with a round tip to fill the hole with chocolate buttercream and then pipe a thin round onto the cupcakes.
3. Use a piping bag with a star tip to pipe the meringue on top of the chocolate buttercream and use a kitchen torch or lighter to toast the meringue.
4. Sprinkle some crush Graham crackers on top of the meringue.
5. Store refrigerated in an airtight container and serve at room temperature or just slightly chilled.