In a large bowl, toss together all the vegetables. Add olive oil, balsamic vinegar, rosemary salt and pepper and toss again until evenly coated.
Arrange in a single layer in a large roasting pan (or baking sheet). If necessary, use two pans to give the vegetables plenty of room to spread out and brown properly. If they’re piled up, they’ll steam rather than roast.
Place in the oven and roast for 35 to 40 minutes, stirring gently two or three times or until vegetables are tender and nicely browned.