Adjust oven rack to lowest position and heat oven to 500 degrees. Toss vegetables of choice all together or by variety with 3 tablespoons of oil and a generous sprinkling of salt and pepper. Turn onto a large (12 x 18 inch) rimmed baking sheet that has been coated with vegetable cooking spray; drizzle with remaining tablespoon of oil and roast until golden and attractively spotty brown, about 25-30 minutes. Serve. (Can be cooled, covered, and refrigerated at least a week.)