Preheat oven to 375 degrees F. Mist donut pan with nonstick cooking spray and set aside.
In a medium mixing bowl, combine the flour, sugar, cocoa powder, chocolate chips, baking soda, and salt.
In a small bowl, whisk together the vanilla, egg, yogurt, milk, and oil.
Stir the wet ingredients into the dry until just combined. Spoon the batter into the donut wells, filling two-thirds full.
Bake for 8 minutes or until the tops spring back when you touch them. Allow the donuts to cool for 2-3 minutes before placing on a wire cooling rack to cool completely.
Meanwhile, whisk together the glazed ingredients until smooth. Dunk the tops of the donuts in the glaze* and place on a wire rack to set, about 5 minutes.