Mix everything in your mixing bowl on low to medium speed for 30 seconds.
Spray doughnut pans with cooking oil, and transfer batter to a gallon size ziploc bag for smooth pouring. Cut the corner off the bag, and squeeze the batter into the doughnut rounds (kind of like squeezing frosting out of a frosting bag). Fill the rounds about 2/3 of the way full. This is enough to make 12 doughnuts.
Bake in a preheated 425 degree oven for about 8 minutes. They get brown more quickly on the bottom, so keep an eye on them.
Let cool for a couple of minutes in the pan, and then transfer to cooling racks.
Mix all frosting ingredients in a saucepan on low to medium heat for just a couple of minutes until the sugar is dissolved.
Then dip the doughnuts in the glaze on both sides (dip the bottom in first, then the top), and then let them rest on the cooling rack till the frosting firms up.
If you want to add sprinkles, add before the frosting firms.