Heat 1 cup broth and pour over chiles. Cover and let soak for 30 minutes. Puree mixture in blender. Saute onion and garlic with the bacon for 5 minutes. Add cumin and cook 2 minutes. Add corn, tortillas, chile sauce, and broth. Bring to a boil, reduce heat and simmer for 5 minutes. Puree soup if desired. Then add milk, return to heat and warm to almost boiling. Serve with a dollop of sour cream.