Sprinkle prepared pork with salt and pepper. Toss to coat evenly.
Preheat wok or a large skillet to a medium high temperature.
Add 2 tablespoons of vegetable oil and heat until hot and shimmering. Swirl the vegetable oil around the wok or skillet until all surfaces, including the sides, are coated.
Place the pork cubes into wok or skillet. Cook until done and white throughout. Do not overcook. Remove pork from the wok or skillet and place it in a clean bowl.
Add green beans, pineapple, green onions, bamboo shoots and bean sprouts to the wok or skillet. Cook, stirring constantly, for 4 - 5 minutes, or until vegetables are slightly tender.
Add pork back to wok or skillet on top of the vegetables.
Pour sweet and sour sauce over the mixture. Stir well to coat evenly. Cook for a few more minutes until hot.
Remove mix and serve over steamed white or brown rice.