Preheat the oven to 350 degrees F (180 degrees C) and grease a mini metal donut pan with melted butter, oil, or baking spray.
In a medium bowl, combine the cocoa powders, chocolate, and hot coffee together. If the chocolate does not fully melt, heat in the microwave in 20 second intervals until fully melted.
In a large bowl, whisk together the flour, sugars, salt, and baking powder.
To the dry ingredients, add the oil, milk, yogurt, egg, and vanilla. Whisk until fully combined.
Add in the chocolate mixture and whisk until fully combined.
Spoon the batter into the prepared donut pan about half way full. Careful not to over-fill!
Bake for 8-10 minutes or until a toothpick inserted comes out clean.
Transfer donuts to wire rack to cool completely before dipping in the chocolate glaze and topping with sprinkles.