Step 1

Preheat oven to 350 F. Grease a donut tin with butter or nonstick spray and set aside.

Step 2

In a large bowl, whisk together flour, cocoa powder, baking soda, salt and espresso powder. Set aside.

Step 3

In a medium bowl, whisk together the egg and sugar until well combined. Add the milk, yogurt, melted butter and vanilla extract. Mix until incorporated and smooth. Pour wet ingredients into bowl of dry ingredients and mix just until combined.

Step 4

Using a piping bag or a spoon, transfer the batter to the prepared donut tin, filling each cavity about three-quarters full. Bake donuts at 350 F for 8 to 10 minutes or until a toothpick inserted into one comes out with little to no crumbs. Allow the donuts to cool in the pan for a couple minutes before inverting them onto a wire rack to cool completely.

Step 5

For the glaze, place the chocolate, heavy cream and butter in a microwave-safe bowl. Heat on 50% power level for one minute. Let the mixture sit for a couple minutes, then stir until smooth. If not smooth, heat for another 30 seconds on 50% power level.

Step 6

Dip the top of each donut in the chocolate glaze and place back on the wire rack to set. Garnish with chocolate shavings if desired.