1. Preheat oven to 350F and line a muffin tin with 12 cupcake liners. In a small bowl, combine the graham cracker crumbs and melted butter until the crumbs are evenly coated. Divide them evenly between the liners, about 2-3 tsp each. Press down firmly. Bake for 5 minutes then remove from the oven.
2. Prepare the chocolate cupcakes. In a large mixing bowl, sift together the flour and cocoa powder, then whisk in the baking soda and salt. In another medium mixing bowl, whisk together the eggs and sugar, then add the oil and vanilla and whisk until thoroughly combined. In a measuring cup, combine the hot water and espresso powder until dissolved. Add the wet ingredients to the dry, alternating between the egg mixture and espresso. Stir just to incorporate (do not over-mix)! Divide the cupcake batter evenly between the cupcake tins (filling 3/4 full). Bake the cupcakes for 12-15 minutes, until a toothpick inserted in the center comes out clean. Mine took 14 minutes. Cool the cupcakes completely on a wire rack.
3. Prepare the strawberry buttercream. While the cupcakes are baking, add the freeze-dried strawberries to a food processor or blender, and pulse them until they’re just a fine crumb. Set aside. In the bowl of a stand mixer fitted with the paddle attachment, or using a handheld mixer, beat the butter until smooth and creamy, 1-2 minutes. Add the powdered sugar, strawberries, cream and vanilla and beat again on low until just beginning to incorporate. Switch to high and run the mixer for 1-2 minutes until the frosting is thickened. Add more cream or powdered sugar, as needed to achieve the right consistency. Transfer the frosting to a piping bag fitted with a large tip (I used Wilton 8B).
4. When the cupcakes have cooled, use a sharp paring knife to cut out a 1″ piece of cake from the center. Discard, or set aside to replace in the cupcake after filling. Using the piping bag of strawberry frosting, fill each cupcake with frosting. Pipe around the edges of the cupcake to create a trimming of strawberry.
5. Prepare the marshmallow meringue. Bring a medium-sized saucepan filled about 2-3″ with water to a gentle simmer over medium heat on the stove. In a heat-proof bowl, whisk together the egg whites, sugar, cream of tartar and salt. Place the heat-proof bowl over the saucepan of simmering water and whisk continuously for about 5 minutes, or until the sugar is dissolved and the mixture reaches a temperature of 140F. If you’ve used the bowl of your stand mixer, place it into the mixer, fitted with the whisk attachment otherwise, empty the mixture into the bowl of your stand mixer. You can also use a handheld mixer, but it will take long! Beat on high for about 5 minutes, or until stiff peaks begin to form.  Transfer the meringue to another piping bag (I used the Wilton 1A tip) and pipe swirls of marshmallow meringue onto the center of your cupcakes. Use a kitchen torch to lightly brown the edges, or place the cupcakes under the oven broiler for a minute or two! Serve immediately.

As mentioned in the blog post above, the meringue begins to break down after the first day. The cupcakes will still be good but the meringue will have a different texture. Store the cupcakes in an airtight container, at room temperature for 1-2 days, or in the fridge for 3-4 days.