1Preheat oven to 450 degrees F (230 degrees C). Lightly spray a cookie sheet with vegetable cooking spray.
2Place the asparagus and mushrooms in a bowl. Drizzle with the olive oil, then season with rosemary, salt, and pepper; toss well. Lay the asparagus and mushrooms out on the prepared pan in an even layer. Roast in the preheated oven until the asparagus is tender, about 15 minutes.
Footnotes
Tip
Aluminum foil can be used to keep food moist, cook it evenly, and make clean-up easier.