Preparation Preheat the oven to 425°F. Toss carrots with oil and salt and pepper to taste in a shallow (1-inch-deep) baking pan. Roast in middle of oven, stirring once, until barely tender, about 20 minutes. Leave oven on. Stir together vinegar and sugar until sugar is dissolved. Drizzle over carrots, shaking pan to coat, then roast until carrots are tender and vinegar is evaporated, 5 to 8 minutes more.