Preheat the oven to 350°F. Line a 12-cup, standard muffin pan with 12 cupcake liners. Set aside.
In a small bowl, whisk together the flour, baking powder, baking soda, salt, and espresso powder. Set aside.
In a large bowl, add the sugar and oil and whisk together well.
Add the eggs one at a time, whisking until just combined.
Pour in the vanilla extract and milk, and stir with the whisk until mixed.
Pour in the brewed coffee, and stir again until combined.
Gradually add the dry ingredients to the wet ingredients, stirring to make sure there are no big lumps (some small lumps are fine). The batter will be thin.
Fill the paper liners with the cupcake batter to the top. Then bake for 20 minutes, or until a toothpick inserted into the center cupcakes comes out clean. Allow the cupcakes to cool on a wire rack.
While the cupcakes are cooling, cream the butter in a large bowl with an electric hand mixer (or in a stand mixer with a paddle attachment).
Add the espresso powder, cocoa powder, and salt, and continue beating.
Slowly add the powdered sugar while continuing to mix with the electric hand mixer, adding the heavy whipped cream when the frosting starts to get thick.
Continue mixing until the buttercream is smooth and thick. Transfer the buttercream to a piping bag with a large star tip (either Wilton 1M or 2D works well.)
Once the cupcakes are cooled to room temperature, pipe the buttercream in swirls on top of the baked cupcakes.
Top the cupcakes off with a chocolate-covered espresso bean and some cocoa powder, optional.
Store in an airtight container.
▪ When you add the dry ingredients to the wet ingredients, the batter may get very lumpy. I used a spatula to stir everything together, and I pressed the large lumps on the sides of the bowl to get them to break apart. You can also gradually sift in the dry ingredients, or use a whisk to mix everything. Some small lumps in the batter are fine, but larger lumps will rise to the tops of the cupcakes and make the cupcakes look lumpy after they bake. ▪ Don’t be afraid to fill the cupcake liners almost to the top with this batter. Because of the extra moisture in these cupcakes (due to the added coffee) they won’t rise too much over the top of the pan.Refer to the article above for more tips and tricks.The calories shown are based on the recipe making 12 cupcakes, with 1 serving being 1 cupcake. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**