In a large pot, heat olive oil, then add onion and garlic; sauté 3–4 minutes or until onion is translucent.
Add the carrots, celery, baby potatoes, mushrooms, and peas into the pot.
Cook for 2–3 minutes.
Add the Italian seasoning, vegetable broth, diced tomatoes, soy sauce, balsamic vinegar, rosemary, and thyme. Stir and bring to a boil.
In a small bowl, whisk together the cornstarch and water to form a slurry mix. Add to the stew and stir.
Turn heat down, cover pot, and simmer for 45 minutes or until veggies are tender.
