Preheat your oven to 425°F.
Spray your donut pan with non-stick baking (or cooking) spray.
In a medium-sized mixing bowl bowl, whisk together the melted butter, buttermilk and beaten eggs.
In a large mixing bowl, sift together the cake flour, vanilla sugar, baking powder, and salt.
Add the wet ingredients to the dry ingredients and stir together until just combined.
Carefully spoon the batter into about 2/3 full. A cleaner way to add the mixture is to pipe the batter into the pan.
Bake for 7-9 minutes, or until the tops of the donuts spring back when lightly touched. (I should’ve baked this 2 minutes less. They still ROCKED)
Allow to cool in the pan for a couple minutes. Remove the donuts onto a rack to finish cooling before you glaze them.
Make the chocolate glaze while the donuts are baking.
You could make this glaze in your microwave or with a double boiler. I did the double boiler method because I don’t own a microwave.
Microwave on 50 % power for about 1 minute, stirring in-between, until melted.
Stir in the 1 teaspoon hot water until the glaze has thickened. You can add another teaspoon hot water if the glaze is too thick.
Then set these gorgeous chocolate gems on the rack to dry. But first add your sprinkles!!