Reduce the apple cider in a small saucepan over medium heat until it measures 1/2 cup, then cool to room temperature.
Preheat your oven to 350°F (175°C) and thoroughly grease a bundt or loaf pan.
In a large bowl, cream the softened butter and sugar until the mixture is light, fluffy, and pale.
Beat in the eggs one at a time, ensuring each is fully incorporated.
In a separate bowl, whisk together the flour, baking soda, salt, cinnamon, and nutmeg.
Gradually add the dry ingredients to the butter mixture, alternating with the sour cream and the reduced apple cider, mixing until just combined.
Pour the batter into the prepared pan.
Bake for 55–60 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for 10 minutes before transferring to a wire rack to cool completely.