Trim and wash asparagus. Preheat oven to 425°F. When oven is hot, spread 1 tablespoon oil on a baking sheet with edges. Heat for 2 minutes; add asparagus. Roast for 15 to 20 minutes (depending on thickness of asparagus), shaking once to turn spears. Pour on balsamic vinegar and serve hot or at room temperature.
Each serving contains about 53 calories, 3 g protein, 4 g fat, 0 mg cholesterol, 5 g carbohydrates, 2 g fiber, and 2 mg sodium.