Pour the cider into a small sauce pan and over medium to medium high heat, reduce the cider to about 1/3 of a cup. This can take a half hour, or longer, so be patient. Remove the now concentrated cider from the stovetop and let cool to room temp.

Sift the flour, baking powder, baking soda, salt, nutmeg, and cinnamon together in a large bowl. Sift again and set aside.

In the bowl of a stand mixer fitted with the paddle attachment, combine the sugars, shortening and melted butter on medium speed until fluffy, about 2 minutes. With a rubber spatula, scrape down the bowl of the mixer.

With the mixer on low, add the room temp yolks, one at a time, stopping and scraping down the bowl as necessary. Add the room temp buttermilk and the concentrated cider and mix until combined. Scrape down the bowl.

With the mixer on low, add the dry ingredients all at once. When only streaks of flour remain, remove the bowl from the mixer and, using a rubber spatula, incorporate the remaining flour. Transfer the dough (which will be very sticky — somewhere between a cookie dough and a cake batter) to a clean bowl and refrigerate for at least 30 minutes.

Heavily flour (I used cake flour) a work surface and your hands. Remove the dough from the bowl, place it on your work surface and pat the dough or roll it out until it is about 1/2" thick. The dough is extremely soft, so be gentle and do not be afraid of using extra flour. Flour a 3 1/2-inch cookie cutter and a 1-inch cutter, and begin cutting out doughnut shapes (cut out all the large shapes first and then go back and cut out the centers with the smaller cutter). Use additional flour if necessary, and re-flour your cutters each time you use them. Transfer the doughnuts to a parchment-lined baking sheet as you work. Once you have cut all of your doughnuts, and holes (I recommend rolling the holes a bit in your hands to make a proper ball), you may re-roll your scraps and cut out additional doughnuts/holes.

Using a pastry brush, lightly brush your doughnuts/holes to remove excess flour. Place the baking sheet of doughnuts/holes in the refrigerator, and refrigerate overnight, or for several hours.

Combine the sugar and cinnamon in a shallow bowl and whisk. Set aside.

When ready to fry, fill a large, heavy pot with 2-inches of oil, attach a candy thermometer to the side of the pot and heat the oil on medium-high heat until the temperature reaches 350 degrees, or a bit above (the temperature will drop when you add your doughnuts, but while frying, you want your temperature to stay at 350).

Line a cooling rack with a thick layer of paper towels, about 4 thick, and place it near your pot.

Once the oil is at temp, carefully transfer a couple of doughnut holes to the oil (you may need to roll them in your hands before placing them in the oil to help them get back their round shape). I fry the holes first so i can see what the temp of the oil is and to get a sense of how long it will take to fry my doughnuts. Fry the holes for 1 to 2 minutes, using wooden chopsticks or any two thin utensils to gently flip the holes over after one side has browned. When both sides are nicely browned, using a slotted spoon, carefully transfer the holes to the prepared cooling rack and gently pat them with additional paper towels. Continue frying the holes and then move onto the doughnuts. Avoid overcrowding.

While still warm, but cool enough to handle, place the doughnuts/holes in the bowl of cinnamon sugar and use a spoon to sprinkle additional topping over the doughnuts until nicely covered.

The doughnuts will keep for a day or two, but they are best eaten on the day they are made.