Apple and Butternut Squash Soup

In a large stock pot over medium heat, add 2 tablespoons butter. Add diced onion and a little salt and cook for about 3 to 4 minutes. Add butternut squash and cook, stirring occasionally, until soft, about 10 minutes. Add the apples and spices and stir until everything is coated. Pour in the vegetable stock and apple cider and bring to a boil. Reduce heat, and let simmer 25 minutes. Puree with a hand blender until creamy and smooth. Add salt and pepper as needed. Add in the last 2 tablespoons of butter right before serving.