Preheat your oven to 400°F (200°C). Carefully slice the spaghetti squash in half lengthwise and remove the seeds. Brush the cut sides with 1 tablespoon of olive oil and season with a pinch of salt and pepper. Place the halves face down on a baking sheet and roast for about 30-40 minutes, or until the flesh is tender and easily shredded with a fork. Once done, let it cool slightly before using a fork to scrape out the strands.

In a large pot, heat the remaining tablespoon of olive oil over medium heat. Add the diced onion, sliced carrots, and celery. Sauté for about 5 minutes, until the vegetables are softened. Add the minced garlic and cook for an additional minute until fragrant.

Pour in the chicken broth and bring the mixture to a boil. Once boiling, reduce the heat to a simmer. Add the shredded chicken, dried thyme, and dried basil. Let the soup simmer for about 10 minutes to allow the flavors to meld together.

Add the cooked spaghetti squash strands to the pot. Stir well to combine and let the soup simmer for an additional 5 minutes. Season with salt and freshly ground black pepper to taste.

Ladle the soup into bowls and garnish with freshly chopped parsley. Serve hot and enjoy the comforting flavors.