Season beef with 1 tbsp corn starch, sugar, light soy sauce, 1 tbsp sesame oil, onion powder, garlic powder, black pepper. Marinate for 30 minutes.
Stir fry beef in pan with oil and butter. Set aside when cooked.
Add oil and butter to same pan.
Stir fry garlic, hoisin sauce, 1 tbsp sesame oil.
Add asparagus and 1 tbsp water and fry for 5 minutes.
Add cooked beef and fry for another 5 minutes.
Dissolve 1 tbsp corn starch in water and add to pan. Let simmer for 5 minutes.
Check for taste and doneness of the beef and asparagus.