In a very large bowl, add hot mashed potatoes, melted butter, vanilla, sugar, milk and sour cream and whisk using a wire whip.

In a separate bowl, mix flour and baking powder.

Use a strong rubber spatula or a wooden spoon, work the flour into the wet potato mixture. We found it easier to get the flour mixed in the bowl, then work it with our hands on the counter to finish. It was a little sticky but workable.

Sprinkle flour on your counter and add the dough ball and flatten with your hands into a large disc.

Flour the top of the dough and your rolling pin and roll to ¼ inch thick. The dough is very soft and rolls very easily.

Use a donut cutter if you have one; we used a 3” cutter. If you don’t own one, cut large circles with a standard cookie cutter then smaller inner circles with a smaller cutter.

In a low deep heavy pan, place shortening and heat until melted then heat to between 360- and 370-degrees F. This is the optimal temperature range for donuts. Try to keep it at this temperature between batches.

Have a sheet tray with a rack standing by.

Mix sugar and cinnamon and place in a pie dish.

Have another sheet tray or serving platter standing by.

Once the oil is between 360- and 370-degrees F, place six donuts in the hot oil and fry for about a minute or so on each side, turning with a spider strainer, tongs or wooden chopsticks. Once browned on both sides, use a spider to transfer to the rack to drain. Total fry time should be between two and three minutes.

If the oil is back up to temperature, start six more to fry.

While the next six are frying, toss the first cooked batch in the cinnamon sugar then move to the serving tray.

Continue until all of the donuts are fried and coated.

Once the oil is back up to heat, fry the donut holes in one or two batches and following the same process, drain then toss in cinnamon sugar.

Feel free to re-roll the scraps and cut more donuts. (We fried the scraps as is, then munched on them while we photographed.)

Serve immediately. We stored extra donuts frozen in zip lock bags.