- Cut steak across grain into thin strips; coat with mixture of cornstarch and soy sauce. Let stand 5 minutes.
- Meanwhile, cut asparagus diagonally into 2-inch lengths, about 1/4 to 1/2 inch thick.
- Heat 2 Tbsp. vegetable oil in wok or large skillet over high heat. Add beef and stir-fry 1 minute; remove. Heat remaining 2 Tbsp. oil in same pan. Add asparagus; stir-fry 2 minutes. Add onion and stir-fry 1 minute.
- Sprinkle in 3 Tbsp. water; stir-fry 1 minute longer. Add beef, black bean sauce and sherry; cook and stir just until all pieces are evenly coated with sauce. Serve with rice.