In a medium saucepan, simmer the apple cider over medium heat until it is reduced to about 1/2 cup, about 15-20 minutes.

Allow to cool for 15-20 minutes, until mostly room temperature

Preheat oven to 350 F.

Grease donut pans with cooking spray.

In a large mixing bowl, whisk together the granulated sugar, brown sugar, sourdough discard, cooled reduced cider, milk, eggs, apple cider vinegar, and vanilla.

In a medium sized mixing bowl, whisk together the flour, apple pie spice, baking powder, baking soda, and salt.

Using a rubber spatula, gently fold the dry ingredients into the wet ingredients until just combined, being careful not to over-mix.

Carefully spoon the batter into the prepared pan, filling each well 2/3 full.

Bake for 10-12 minutes, until golden brown and the tops are set.

In a small bowl, mix together the cinnamon sugar topping.

When the donuts are done, allow them to cool for 5 minutes in the pan before using a rubber spatula to gently remove. You want them cool enough to handle, but still warm.

While warm, dunk the donuts in the cinnamon sugar coating, turning and tossing to coat.

Enjoy!