1. Dice beef, add a spoonful of soy sauce, a spoonful of cooking wine, half a spoonful of black pepper, a spoonful of starch and a spoonful of oil, and marinate for 10 minute. ?

2. Dice the pineapple and soak it in salt water for 5 minutes. ?

3. Add beef in hot oil, stir-fry until it changes color, then add pineapple and stir-fry for 1 min.