Preheat oven to 350°. Fill 2 cupcake pans with paper liners.
Using a food processor, pulse the graham crackers into crumbs. Or just crush them by putting them in a plastic bag and crushing them. Pour into a medium bowl and stir in sugar and melted butter until combined. Spoon 1 Tablespoons of crust into each cupcake liner. Press down tightly to create a tight and firm crust. Bake for 5 mins in the oven. Let cool.
Combine flour, cocoa, baking soda, baking powder, salt in a bowl. Set aside.
Beat eggs and sugar together. Then mix in vanilla, water and oil. Gradually add in the flour mixture and buttermilk. Spoon evenly into each cupcake liner on top of the graham cracker crusts, filling the liners ¾ of the way.
Bake cupcakes for 25-28 minutes or until a toothpick inserted in the center comes out clean.
Remove from the oven and allow to cool completely. Sprinkle with graham cracker crumbs.
Make the meringue: Place egg whites, sugar, and cream of tartar in a heatproof bowl. Set bowl over a saucepan filled with two inches of simmering water. Do not let it touch the water. (You can use a double boiler if you have one.) Whisk constantly until sugar is dissolved, about 4 minutes.
Transfer the mixing bowl to an electric mixer fitted with a whisk attachment. Add the vanilla. Beat on high speed for 5-6 minutes until stiff glossy peaks form.
Pipe onto cooled brownie cupcakes. If available use a kitchen torch to toast.