In a small saucepan, pour in 1 cup of fresh apple cider and bring to a gentle simmer over medium heat. Allow the cider to reduce until you have about ½ cup left, which should take around 15 to 20 minutes. Stir occasionally to prevent burning, then remove from heat and let it cool.

In a large mixing bowl, combine the melted butter, granulated sugar, and brown sugar. Whisk in the eggs, sour cream, vanilla extract, and cooled apple cider until smooth.

In a separate bowl, whisk together the all-purpose flour, baking powder, baking soda, cinnamon, nutmeg, and salt.

Gently fold the dry ingredients into the wet mixture, mixing until just combined. Take care not to overwork the batter.

Preheat your oven to 350°F (175°C) and grease a 9x5 inch loaf pan. Pour the batter into the pan and spread it evenly.

Bake for 45 to 50 minutes, checking for doneness with a toothpick around the 45-minute mark.

After baking, let it cool in the pan for about 10 minutes before inverting onto a wire rack.

While still warm, brush the top with melted butter. Combine granulated sugar and cinnamon, and sprinkle over the bread.