Pour olive oil in a large stockpot. Brown turkey pieces over medium heat in large stock pot (or broil in the oven) until golden if using necks/wings.
Add remaining ingredients to a large stock pot or slow cooker. Cover and simmer for 45 minutes to 1 hour on the stove (or 10-12 hours on low in the slow cooker).
Strain the broth through a cheesecloth to remove all turkey and vegetables. Return broth to the pot and simmer an additional 30-45 minutes to reduce.
Allow to cool slightly and skim off any fat.
Cool broth and refrigerate up to 3 days or freeze up to three months.
(Nutrition information provided is an estimate and will vary based on cooking methods and brands of ingredients used.)