Chop pork shoulder into 3/4" cubes; place in freezer bag; freeze.
To prepare: thaw pork cubes before cooking. Heat salad oil in wok until hot; carefully add cubed pork. Stir-fry until completely cooked; remove pork from wok and reserve.
Add onions, cabbage and bean sprouts to oil remaining in wok; stir-fry just until tender-crisp. Remove vegetables from wok and reserve with pork.
Add cooked rice to oil remaining in wok (add 1 to 2 tablespoons oil if necessary) and fry lightly until each grain is separate, coated and hot. Return vegetables and pork to wok and mix with rice until hot; add sesame oil and soy sauce to taste.
Push rice mixture up wok sides and add beaten egg to bottom of wok; cook and stir until set. Toss egg lightly with fried rice; serve hot.