Step 1: In a small saucepan, simmer the 2 cups of apple cider over medium heat until it has reduced to exactly 1/2 cup. This should take about 20-25 minutes. Let it cool completely before using in the apple cider donut cake with maple glaze recipe.
Step 2: Preheat your oven to 350°F (175°C) and generously grease and flour a 10-cup Bundt pan, ensuring every crevice is covered to prevent sticking.
Step 3: In a medium bowl, whisk together the flour, baking powder, baking soda, cinnamon, nutmeg, and salt until well combined.
Step 4: In a large bowl or stand mixer, cream the softened butter with the granulated sugar and brown sugar for 3-5 minutes until the mixture is light and fluffy.
Step 5: Add the eggs one at a time, beating well after each addition. Mix in the vanilla extract and the cooled, reduced apple cider.
Step 6: Gradually add the dry ingredients to the wet ingredients in three parts, alternating with the sour cream. Start and end with the dry ingredients. Mix until just combined.
Step 7: Pour the batter into the prepared Bundt pan and smooth the top with a spatula. Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Step 8: Allow the cake to cool in the pan for 15 minutes before carefully inverting it onto a wire rack to cool completely.
Step 9: While the cake cools, whisk together the powdered sugar, maple syrup, and milk until a thick, smooth glaze forms. Drizzle the glaze over the cooled apple cider donut cake with maple glaze recipe before serving.