Preheat the oven to 350°F and line a 12 cup cupcake pan with cupcake liners.
Whisk the cake flour, baking powder, espresso powder, and salt together in a large bowl.
In a separate bowl, whisk the melted butter, sugar, brown sugar, eggs, and vanilla together until combined.
Stir in about half of the flour mixture. Then stir in the brewed coffee and the rest of the flour mixture and mix until fully combined.
Pour about ¼ cup of batter into each cupcake liner (they should be about halfway full).
Bake at 350°F for 18-22 minutes or until a cake tester comes out clean.
Remove from pan and let cool on wire rack.
Let cupcakes cool completely before frosting.
Espresso Buttercream
In a stand mixer fitted with the paddle attachment, cream together the softened butter, powdered sugar, and espresso powder until smooth and creamy.
Add in 1-2 tablespoons of cream as needed to thin out the buttercream, then beat for 4-5 minutes on high speed until light and fluffy.
Frost cooled cupcakes. I used a Wilton 1M tip for these photos.
Top with chocolate covered espresso beans and an extra sprinkle of espresso powder if desired!
Notes
For chocolate mocha cupcakes, reduce the flour by ¼ cup and add in ½ cup of unsweetened cocoa powder.
These cupcakes will last in the fridge for up to 3 days. However, they taste best when served at room temperature! I like to let them sit at room temperature for about an hour before serving.