Preheat the oven to 350F. Line a 12 cup muffin tin with cupcake liners.
In a small bowl, combine the cocoa powder and espresso and whisk until thoroughly incorporated. Set aside.
In a medium bowl, combine the flour, baking soda, baking powder, and salt. Whisk to combine.
Place the sugar and the butter into a saucepan over low heat. When the butter is almost melted, transfer the mixture to a bowl of a stand mixer fitted with a paddle attachment.
On medium low speed, beat the butter mixture until it is room temperature.
Adjust the speed to low. Add the eggs, one at a time, scraping the bowl after each addition. Add the vanilla.
Add the chocolate coffee mixture. Scrape the sides of the bowl.
Add the flour mixture in three batches, alternating with the sour cream, mixing only until just combined after each addition.
Remove the bowl from the mixer and scrape down the sides and the bottom to make sure that all the ingredients are fully mixed.
Divide the batter among the cupcake liners. Bake the cupcakes for 16-19 minutes or until a toothpick comes out with a few stray crumbs.
Cool for 10 minutes in the pan. Transfer the cupcakes to a cooling rack to cool completely.