1. In a large pot, heat some oil over medium heat. Add the diced chicken breast and cook until browned.
2. Add the chopped onion, minced garlic, sliced carrots, and sliced celery. Cook until the vegetables are tender.
3. Pour in the chicken broth and bring to a boil. Add the rice, salt, black pepper, and dried thyme. Reduce heat and let it simmer for about 20 minutes, or until the rice is cooked.