In a large stock pot heat chicken fat (or oil) on high. Add in the carrots, celery, onions, and butternut squash. Place lid on the pot and sweat out vegetables for 5 minutes. Mix and reduce heat to medium. Place the lid back on and sweat for an additional 5 minutes.
Next, add in the butternut squash puree, ground sage, chili powder, thyme leaves, crushed rosemary, garlic powder, and salt and pepper to taste. Mix well and add in the chicken stock.
Let cook for 10 minutes on low then mix in the great northern beans and shredded chicken. Let simmer on low for one hour. Just before serving mix in a dash of nutmeg, fresh parsley and sliced green onions