1 small butternut squash, cubed
2 red bell peppers, seeded and diced
1 sweet potato, peeled and cubed
3 Yukon Gold potatoes, cubed
1 red onion, quartered
1 tablespoon chopped fresh thyme
2 tablespoons chopped fresh rosemary
1/4 cup olive oil
2 tablespoons balsamic vinegar
salt and freshly ground black pepper