In a large saucepan, over medium-high heat, pour the apple cider and cook until the cider is reduced to 1 cup, about 20 minutes. Pour the cup of reduced apple cider in a small bowl and place into the refrigerator to cool.
Meanwhile, in a medium bowl, combine granulated sugar and 2 tablespoons of cinnamon. Set aside.
Next, in a large mixing bowl, add the flour, brown sugar, baking powder, salt, baking soda, nutmeg, and remaining cinnamon.
In a small bowl, lightly whisk the eggs. Add in the melted butter and cooled apple cider. Whisk until well blended. Pour over the flour mixture in the large mixing bowl.
Using a silicone spatula, stir to combine the wet and dry ingredients just until moist. Cover the bowl with a kitchen towel or plastic wrap and place in the refrigerator. Chill for 1 hour.
Flour a large work surface and place the donut dough in the center. With a lightly floured rolling pin, roll the dough into a large disc with a 1/2-inch thickness.
Use a traditional donut cutter or a 2 1/2 inch round biscuit cutter with a 1-inch biscuit cutter for the center hole to cut your donut rounds.
In a large pot, heat the oil over medium-high heat until it has reached a temperature of 375 degrees on a digital instant-read thermometer.
Working in batches of 4, carefully lower the donut rounds into the hot oil. Allow the donut to cook until golden and crispy, about 45 seconds to 1 minute per side.
Carefully remove the hot donuts with a slotted spoon to a paper-towel-lined plate, allowing excess oil to drain, for about 30 seconds. Next, quickly transfer the donuts to the bowl with the cinnamon-sugar mixture.
Using a spoon, coat the warm donuts in the cinnamon-sugar mixture. Place donuts on wire cooling rack to cool slightly. Serve immediately.
You can purchase your donut cutter or round mini cookie cutters set online.
You may discard the center donut hole dough or you may fry them. If you choose to fry the donut holes, fry them for 30-seconds per side.