1. Affix the S-blade to your food processor.
2. Trim rough ends from celery. Roughly chop and add to the bowl of the food processor.
3. Trim roots and green ends from green onions. Roughly chop whites and add to the food processor.
4. Peel and trim the cloves from one head of garlic. Add to the food processor.
5. Add parsley leaves and duck fat to the food processor with sea salt and black pepper. Process mixture until smooth while adding white wine through the processor spout.
6. Run your hands between the skin and meat of the bird to loosen the skin without tearing.
7. Take small handfuls of the paste and take care to cover every meaty surface with the bright green mixture.
8. Neatly replace the skin over the rubbed bird.
9. Brush skin of the bird with equal parts duck fat, chicken broth and white wine, and use this mixture for basting as the bird cooks covered.
10. Roast the turkey covered at 325F for 12-15 minutes per pound, or until the thickest part of the thigh reaches 165F when you insert a meat thermometer.
11. If cooking a pasture-raised bird, monitor frequently towards the end as it may cook faster than a conventional turkey.
12. Remove the cover for the last 30 minutes of cooking time to brown.