Preheat oven to 350°F. Line muffin pan with cupcake liners and set aside.
In a large bowl, stir together flour, cocoa powder, baking powder, baking soda, and salt.
Add in the sugar and brown sugar stir until combined.
Add the oil, buttermilk, egg, and vanilla extract. Mix until just combined.
Fill cupcake liners ¾ of the way full.
Sprinkle graham cracker crumbs on top of the batter.
Bake for 21-23 minutes. Cool.
For the Frosting
Fill a medium saucepan with ~1 inch of water. Bring to simmer.
In a large bowl whisk egg whites, sugar, cream of tartar and salt.
Place bowl over the simmering water. Make sure the bowl does not touch the water.
Whisk constantly until it reaches 120 degrees.
Remove the bowl from the water and stir in vanilla. Mix until it forms slightly stiff peaks.
Spread or pipe onto cupcakes using a star tip.
Toast using a kitchen torch or your broiler. I broiled mine for 2 minutes.
Garnish with graham crackers and Hershey bars.
Notes
Ingredient Notes and Shopping Tips
Cocoa Powder: Use unsweetened natural cocoa powder. I used Hershey's. Avoid Dutch Process cocoa powder which will not react as well with your learners to give your cupcakes height.
Baking Powder: Be sure to replace yours every 6-12 months as it loses effectiveness.
Baking Soda: Baking soda will react with buttermilk to help the cupcakes rise.
Buttermilk: If you don't have buttermilk on hand, you can make your own. Use one tablespoon of lemon juice per vinegar per cup of milk.
Flour: Spoon flour into your measuring cup. Never dip your cup into the flour, or you will get too much.
Egg Whites: Use room temperature egg whites. I like to allow my eggs to sit out for around 30 minutes.
Cream of Tartar: This will help stabilize our frosting, so don't skip it. Even though it is a baking ingredient ,it can usually be found next to the spices.
Graham Cracker Crumbs: Approximately 14 graham crackers are needed to make 1 cup of crumbs.
Tips
Don't Over Mix: Mix until the ingredients are just combined. Overmixing will lead to a tough, dense cake.
Don't Over Bake: Bake until a toothpick inserted in the center comes out clean or with just a few moist crumbs. Overbaking will lead to a dry cupcake.
Perfect Meringue: Use a clean bowl. Also, ensure there is no egg yolk in your egg whites, or they will not whip up as expected. Easily separate eggs by pouring back in forth between the shells. There are also a number of egg separators you can buy on Amazon.
Doneness: If you don't have a candy thermometer, go by feel. It should feel silky smooth and not at all grainy.
Broil Carefully: If using the boiler, place the cupcakes into the oven on the lowest rack away from the broiler grills. Keep a close eye on them too. They can go from toasty to burnt quickly.