A butter-enriched balsamic reduction sauce brings out the best in asparagus.
- Preheat the oven to 450°F.
- Combine the vinegar and sugar in a small saucepan over medium-high heat. Bring to a boil and cook until reduced by half, about 4-5 minutes. Remove from the heat and swirl in the butter until melted; reserve.
- Toss the asparagus, oil, salt, and pepper in a large bowl. Arrange in a single layer on a large nonstick baking sheet. Set in the center of the oven and roast until asparagus is crisp tender, shaking pan occasionally, 9-10 minutes. Transfer to a serving platter and drizzle with balsamic mixture.