Preheat oven to 400F. Grease a large, shallow casserole dish with 1 tablespoon of oil.
Toast bread cubes on a large baking sheet in the oven until golden brown, 5-10 minutes. Set aside in a large bowl.
Turn oven down to 350F.
Heat 2 tablespoons olive oil in a large skillet on medium heat. Sauté onions, garlic and celery until tender.
Using a rubber spatula, transfer the veggie mixture to the bowl of bread crumbs. Add cranberries (if using) parsley, sage, thyme, salt and pepper. Stir until until everything is well-mixed.
Add 2 cups vegetable stock, and stir until it is absorbed. Add more stock as needed so that the mixture is moist and clumping together, but not soggy. Transfer to casserole dish.
Drizzle 1 tablespoon of olive oil over the mixture, then bake covered for 25 minutes.
Uncover and bake another 10-15 minutes to form a crusty top.
Optional: Instead of using a casserole dish, get creative by baking your stuffing in hollowed-out pie pumpkins or other large gourds. All directions remain the same, except you should place your pumpkin on a baking sheet before baking in the oven to prevent it from making a mess or sticking as it softens, then bake for about 1 hour.