In the bowl of a standing mixer, pour warm milk, sugar and yeast. Let stand until yeast starts to foam. About 10 minutes. Attach dough hook to standing mixer while yeast is activating.
In a medium mixing bowl, whisk together the flour and salt.
Add flour mixture, butter and egg yolks to the yeast mixture and beat on medium speed until it comes together and forms a ball. Just about 3-5 minutes. Cover the bowl and and allow the dough to rise in a warm place for 1 hour.
Spray a sheet tray with non stick cooking spray and set aside. Transfer the dough to a lightly floured work surface and roll out to a 1/2" thickness. Using a 2"-3" donut cutter (you can also use a drinking glass or biscuit cutter to cut out your donuts and a plastic bottle cap to cut out the holes), cut out donuts and transfer them and their holes to the prepared baking sheet, spacing them 1" apart. Spray the tops of the donuts and holes with nonstick cooking spray and cover with plastic wrap. Let stand in a warm place until they have almost doubled in size, about 30 minutes.
Using a deep fryer or dutch oven, heat oil to 350º. Line a baking sheet with paper towels or brown paper and set aside.
Working in batches, fry the donuts and donut holes until lightly golden brown, about 1 minute per side. Transfer to the paper lined baking sheet and let cool for 10 minutes before glazing.
To make the glaze: In a large mixing bowl using a hand mixer or whisk, mix all ingredients together. Mixture should be thin. Add more hot water if needed to thin out the glaze. Keep glaze warm until ready to use.
Dip the donuts, one at a time, into the warm glaze, covering the top half of each donut with glaze. Dip glaze side down into a bowl filled with your favorite sprinkles and place on a tray to set for
10 minutes. Serve immediately.