Preheat the oven to 375°F (190°C).

In a mixing bowl, combine the stuffing mix, chicken broth, diced celery, diced onion, melted butter, thyme, sage, salt, and pepper.

Rinse the chicken under cold water and pat it dry with paper towels.

Carefully spoon the stuffing mixture into the cavity of the chicken.

Rub the outside of the chicken with olive oil and season generously with salt and pepper.

Transfer the stuffed chicken to a large baking dish, breast side up.

Bake in the preheated oven for about 1 hour and 15 minutes, or until the internal temperature reaches 165°F (75°C).

Once cooked, let the chicken rest for 10 minutes before carving.