These baked doughnuts are moist, flavorful and topped with a delicious coffee buttercream. It's the perfect treat for breakfast or dessert!
Preheat oven to 350F. Spray six-cavity doughnut pan with non-stick cooking spray. Set aside.
In a medium bowl whisk together flour, cocoa powder, baking soda and salt.
In a separate medium bowl whisk together butter, egg, sugars, instant espresso powder, vanilla extract and buttermilk until combined. Spoon into a large piping bag then cut the tip and pipe into prepared pan. It should be about 2/3 full. With leftover batter you can either use another donut pan or use a mini cupcake pan to make doughnut holes.
Bake for 9 minutes, until a toothpick inserted into the middle comes out clean. Let cool in pan for about 5 minutes then transfer to wire rack to cool completely.
In the bowl of a standing mixer fitted with the paddle attachment, beat the butter on medium speed until smooth and creamy. Gradually add powdered sugar and heavy cream, mixing on low until combined. Mix in the extract and salt. Use a rubber spatula to scrape down the sides and bottom of the bowl, then mix on medium-high for 1 – 2 minutes.
Transfer to a piping bag, cut the tip and create a flower shape on top of the cooled doughnuts.
To garnish, dust with cocoa powder.