01 -
Set your oven to 350°F (175°C). Place cupcake liners into a 12-cup muffin pan and get it ready.
02 -
Stir together the flour, cocoa powder, baking soda, baking powder, and salt in a medium bowl until it’s smooth with no clumps.
03 -
In a big bowl, whisk eggs, sugar, oil, and vanilla until they’re all mixed and smooth.
04 -
Gently fold the dry mixture into the wet one in parts, alternating with the buttermilk. Start and end with the dry ingredients (use about a third of the dry mix, then half the buttermilk, and so on). Only mix just enough to blend.
05 -
Pour in the hot coffee or heated water slowly, stirring until the mix is smooth. It’ll look a bit thin—don’t worry about it.
06 -
Scoop the batter evenly into the lined pan, filling each liner no more than halfway to two-thirds of the way full.
07 -
Put the pan in the oven and cook for 18-20 minutes. Check by inserting a toothpick—it should come out clean or with a little moist crumb.
08 -
Take the cupcakes out and let them rest in the pan for 5 minutes. Then move them to a cooling rack to finish cooling off completely before frosting.
09 -
Put chocolate chips in a heat-safe bowl. Heat the cream on the stove until hot but not boiling, then pour it over the chocolate. Let it sit for 2 minutes before whisking until it’s all melted and shiny. Cool at room temperature.
10 -
Using an electric mixer, blend the softened butter in a bowl until fluffy. Add powdered sugar, vanilla, and salt, mixing on low to combine, then turn up to medium-high until creamy.
11 -
Mix the cooled chocolate mixture with the buttercream using the mixer on medium speed until it’s all blended and has a fudgy texture.
12 -
Frost the cooled cupcakes using a piping bag or a spatula. If the frosting is too runny, pop it in the fridge for about 10-15 minutes before using.
13 -
Top the frosted cupcakes with chocolate chips, sprinkles, or whatever fun toppings you like.
14 -
You can serve them right away, or keep them in an airtight container. They’ll last at room temp for a day or two, or in the fridge for up to five days.