Mix the flour, cocoa powder, and baking powder together. Whisk in the salt and sift.

In a separate bowl, beat together the sugar, butter, and eggs on high speed for 2 - 3 minutes.

Add in the sour cream and water and continue mixing on medium speed until well blended and smooth.

Slowly add in the dry ingredients and mix until fully incorporated.

Cut a large piece of plastic wrap. Transfer the dough to the plastic wrap, cover, and refrigerate for one hour.

Lightly dust a work surface with flour. Place the dough on the floured surface and roll it out ½ inch thick.

Use a round 3-inch cookie cutter to cut the doughnuts and a ¼ inch cutter to make the holes. Place the doughnuts on a 16-inch cookie sheet. Cover and refrigerate for another 30 minutes.

Pour oil into a deep fryer and heat to 360 degrees.

Place 2 - 3 donuts at a time in the fryer and cook until both sides are golden brown.

In a small pot, whisk together the milk, powdered sugar and salt in a medium bowl. Add in the melted chocolate. Heat.

Dip the tops of the donuts inside the glaze and garnish with extra chocolate shavings.