In a small saucepan, simmer apple cider over medium heat, stirring occasionally, until it reduces to ½ cup, about 10-12 minutes. Set aside to cool.
Preheat oven to 350℉. Lightly grease two 6-cavity donut pans with baking spray or butter and set aside.
In a large mixing bowl, whisk Prairie Farms Buttermilk, reduced cider, egg, vanilla, melted Prairie Farms Unsalted Butter, brown sugar, and granulated sugar until smooth.
In a separate bowl, whisk flour, baking powder, baking soda, cinnamon, ginger, salt, and nutmeg.
Add dry ingredients to wet mixture and stir gently until just combined (do not overmix).
Spoon or pipe batter evenly into prepared donut pans, filling each cavity about ¾ full.
Bake at 350° for 13-15 minutes, or until a toothpick inserted into a donut comes out clean.
Let donuts cool in their pans for about ten minutes, then carefully remove them.
In a shallow bowl, mix sugar and cinnamon for coating. While donuts are still warm, press or roll them in cinnamon sugar until coated.