Heat oil in a medium pot over medium heat. Add onion and cook until soft, about 4 minutes.
Add garlic, bell pepper, and celery and cook for two more minutes, stirring.
Add Italian seasoning, tomatoes, tomato sauce, pinto beans, vegetable broth, yeast flakes, cumin, smoked paprika, salt, and chili.
Cover the pot and bring to a boil. Reduce to a simmer and cook for 30 minutes or until chili is at your desired thickness. Season with salt and pepper to taste.