Preheat oven to 325°F (160°C).

Rinse and pat dry the turkey. Rub with olive oil, salt, and pepper.

Place turkey in a roasting pan and roast for 3-4 hours, or until a meat thermometer inserted into the thickest part of the thigh registers 165°F (74°C).

Let the turkey rest for 20 minutes before carving.

In a large skillet, melt butter over medium heat. Add celery and onion; cook until softened, about 5 minutes.

Add bread cubes, chicken broth, sage, thyme, salt, and pepper. Stir to combine.

Bake in a preheated oven at 350°F (175°C) for 30 minutes, or until golden brown.