Start by pouring 2 cups of fresh apple cider into a saucepan. Heat over medium-low heat, stirring occasionally, until the cider reduces by about half, approximately 20 minutes. Once ready, remove it from heat and let it cool while you prepare the donut batter.

Preheat your oven to 350°F (177°C). Grease each cavity of a donut pan with non-stick cooking spray or butter.

In a large mixing bowl, combine 2 cups of all-purpose flour, 1 tablespoon of baking powder, 1 teaspoon of baking soda, 1 teaspoon of cinnamon, 1 teaspoon of apple pie spice, and ½ teaspoon of salt. Whisk together until evenly blended.

In a separate bowl, whisk together ½ cup of melted unsalted butter, 1 large egg, ¾ cup of brown sugar, ¼ cup of granulated sugar, ½ cup of milk, and 1 teaspoon of vanilla extract. Add the cooled apple cider reduction and stir until combined.

Gently pour the wet ingredients into the bowl with the dry ingredients. Using a spatula, gently fold the mixture together until just combined.

Transfer the batter into a zip-top bag and snip off one corner. Carefully pipe the batter into the greased donut pan, filling each cavity about halfway.

Place the filled donut pan in the preheated oven. Bake for 10-11 minutes, or until the edges are golden and a toothpick comes out clean.

Once baked, let the donuts cool for about 5 minutes in the pan, then transfer to a wire rack.

Prepare a cinnamon sugar mixture by combining equal parts granulated sugar and cinnamon in a shallow dish.

Melt 4 tablespoons of butter, dip each donut in the melted butter, then roll in the cinnamon sugar mixture.