Begin by pouring 6 cups of apple cider into a medium saucepan. Simmer over medium heat for 40-50 minutes, stirring occasionally, until it reduces down to about 1 cup.

In a large mixing bowl, whisk together 2 cups of all-purpose flour, 1 teaspoon each of cinnamon, nutmeg, and allspice, along with 1 teaspoon of baking powder, 1/2 teaspoon of baking soda, and 1/2 teaspoon of salt.

In a separate mixing bowl, beat together 1 cup of softened unsalted butter, 1 cup of granulated sugar, and 1/2 cup of brown sugar using an electric mixer on medium speed for about 2 minutes.

Add 3 large eggs, one at a time, mixing well after each addition. Then, blend in 1 teaspoon of vanilla extract.

Stir in 1/2 cup of buttermilk, 1/2 cup of sour cream, the cooled apple cider reduction, and 1/2 cup of apple butter.

Gradually fold the prepared dry ingredients into your wet mixture until just combined.

Preheat your oven to 350°F (175°C) and pour the batter into a greased 9x9 inch baking pan, smoothing the top.

Bake for 48-52 minutes or until a toothpick inserted in the center comes out clean. Allow the cake to cool in the pan for at least 10 minutes before transferring it to a wire rack.

Make the caramel sauce by simmering the apple cider reduction, 1/2 cup of brown sugar, and 4 tablespoons of unsalted butter in a small saucepan.

In a mixing bowl, beat 1/2 cup of softened unsalted butter, then add 8 ounces of softened cream cheese, blending until smooth.

Gradually add 4 cups of powdered sugar, mixing until you achieve a creamy and spreadable frosting.

Once the cooled Apple Cider Cake is ready, poke holes all over the top with a toothpick, pipe in the caramel, and frost with cream cheese frosting.