Either spoon the batter into the greased donut pans and fill to almost the top or put all the batter into a piping bag or a zip top bag with the corner snipped off and pipe the batter into the donut pans.
Combine all the glaze ingredients in a bowl and use a whisk to combine. Take one donut and dip the entire thing in the glaze. Do it quickly. Wipe the bottom and place on the cooling rack, bottom side down.