Preheat oven to 230 degrees C (450 F).

Line a baking sheet with aluminum foil. Spread asparagus and drizzle with olive oil. Toss to coat well.

Add hoisin sauce. Toss again to cover asparagus evenly with the sauce. Arrange asparagus so that the thicker stems are near the rim of the baking sheet. Leave some space between the asparagus spears, so they will crisp up, not become steamed.

Bake for 5 minutes. The asparagus should be almost cooked through, but still a bit chewy. If you’re using thicker asparagus, you might need to add another minute or two. Toss again and return the tray to the oven. Turn on broiler and cook for another 2 minutes, or until the sauce is slightly caramelized. You should watch it closely after turning on the boiler. When the asparagus is done, transfer the it to a serving tray immediately so that it stops cooking.