Preheat the oven to 350°F (180°C) and line a 12-well muffin/cupcake tin with paper liners.

In a large bowl, whisk together the flour, black cocoa powder, sugar, baking soda, and salt.

Add the egg, vanilla, vinegar, vegetable oil, and buttermilk and whisk until well combined.

Gradually add the hot coffee, mixing until smooth and combined. Don't over mix. The batter will be very thin.

Fill the cupcake liners ⅔ of the way full with batter (scrape out every last drop with a silicone spatula). Bake for 18-20 minutes or until a cake tester inserted into the center comes out clean. A few moist crumbs are ok as long as there's no wet batter.

Cool in the pan for 10 minutes then use a knife to gently pop them out of the tin. Transfer them to a wire rack to cool completely before frosting, about 50 minutes.

In a large bowl using an electric hand mixer (or stand mixer fitted with a paddle attachment), beat the softened cream cheese on medium-high speed for 1 minute until creamy, scraping down the bowl as needed.

Add the powdered sugar, black cocoa powder, vanilla, and salt. Pulse on low speed a few times then continue mixing on low speed until well combined. This prevents the sugar from flying everywhere.

Add the heavy cream and mix until smooth. Transfer to a piping bag and pipe the frosting onto the cooled cupcakes (we use Wilton's 1M tip). Decorate as desired and enjoy!