- Chop the scallion; remove the seeds off the tomatoes and then chop it; combine the corn flour with the little water; cut the beef into thin strips and season them; peel the pineapple and then remove the brown eyes from the flesh, then cut the flesh into round slices and remove the core.
- Heat the wok and then heat the oil in it. Now put the meat, ginger and scallions in the wok and stir-fry until colored. Discard the any excess fat.
- Now put the stock, sauce, vinegar, sugar, and juice in the wok, stir. Then put the tomatoes and pineapple, lower down the heat and cook for a few minute.
- Now gradually add the corn flour mixture to the wok, stirring continuously until it reaches your required consistency.
- Transfer to the serving plates and serve 'Stir-Fried Beef With Pineapple' with the rice.