Step 1: Simmer 2 cups of apple cider in a small saucepan over medium heat for about 15-20 minutes until reduced to exactly 1/2 cup. Allow it to cool completely before proceeding.
Step 2: Preheat your oven to 375°F (190°C) and line a 12-cup muffin tin with paper liners or grease well with non-stick spray.
Step 3: In a large bowl, whisk together the all-purpose flour, baking powder, baking soda, salt, cinnamon, nutmeg, and cloves until well combined.
Step 4: In a medium bowl, whisk together the cooled apple cider reduction, dark brown sugar, oil, egg, and vanilla extract until the mixture is smooth.
Step 5: Pour the wet ingredients into the dry ingredients. Use a spatula to gently fold the mixture together until just combined. Do not overmix; a few small lumps are perfectly fine.
Step 6: Divide the batter evenly among the 12 muffin cups, filling each about 3/4 full.
Step 7: Bake for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out clean or with just a few moist crumbs.
Step 8: Let the muffins cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.