Preheat your oven to 350°F (175°C).
Rinse the turkey inside and out under cold water, then pat it dry with paper towels.
In a small bowl, mix together salt, black pepper, garlic powder, onion powder, paprika, thyme, rosemary, and sage.
Rub the melted butter all over the turkey, making sure to get under the skin where possible. Then evenly sprinkle the seasoning mixture over the turkey.
Stuff the cavity of the turkey with the chopped celery, carrots, onion, and apple.
Place the turkey in the plastic roasting bag according to the bag manufacturer’s instructions. Tie the bag closed and cut a few small slits in the top to allow steam to escape.
Place the bagged turkey in a large roasting pan and put it in the preheated oven.
Roast the turkey for about 3 to 3 1/2 hours, or until the internal temperature in the thickest part of the thigh reaches 165°F (74°C).
Once done, carefully remove the turkey from the oven and let it rest in the bag for at least 20 minutes before carving.Variations & Tips
For a citrus twist, add wedges of oranges and lemons inside the turkey cavity along with fresh herbs like rosemary and thyme. If you’re looking for a deeper, smokier flavor, try incorporating a teaspoon of smoked paprika into the seasoning mix. You can also add a few strips of bacon over the turkey breast before placing it in the bag for an extra layer of flavor.