In a large bowl, combine onion, broccoli, squash, and tofu. In a small bowl, combine remaining ingredients (vinegar through thyme). Whisk together well, and then cover veggies and tofu in mixture.
Make sure it’s fully saturated (gently mix so you don’t break the tofu), cover with plastic wrap, place in refrigerator, and marinate for at least 2 hours or overnight.
At time of cooking, preheat the oven to 400 degrees.
Line a large baking sheet with parchment paper. Remove veggies and tofu from refrigerator, and evenly arrange on the baking sheet.
Bake for 30 minutes or until veggies are fork tender.