Preheat the oven to 350°F and line a standard muffin tin with cupcake liners.
In a large bowl, sift together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a separate bowl, whisk together the egg, sour cream, vegetable oil, and vanilla until combined.
Add the wet mixture to the dry ingredients and mix until combined. Then add the hot coffee or water and carefully stir to combine.
Fill each cupcake liner halfway full, and bake for 13-15 minutes.
While the cupcakes bake, prepare the ganache. Place the chopped chocolate in a heat-proof bowl.
Heat the heavy cream until it almost simmers, then pour it over the chocolate and let it stand for 1 minute.
Stir the mixture from the center, slowly moving outward until it comes together completely.
Let the ganache cool to room temperature until it thickens, similar to the consistency of peanut butter.
Once cupcakes have cooled, use a pairing knife to create a small hole in the center of each cupcake to fill with ganache.
Prepare the strawberry Swiss meringue buttercream by warming egg whites and sugar in a double boiler until the sugar has dissolved.
Transfer the warm mixture to a stand mixer and beat until stiff peaks form.
Gradually add softened butter one piece at a time until fully incorporated, then add vanilla and strawberry powder.
Pipe the strawberry buttercream onto each cupcake as desired.
