2 1/2 lb. lean pork
1/4 c. soy sauce
1 1/2 tbsp. water
2 tsp. sugar
1 egg yolk
10 tbsp. cornstarch
3 c. vegetable oil
1 lg. yellow onion
8 green onions
1 red or green pepper
4 oz. fresh mushrooms
2 stalks celery
1 med. zucchini
3 tbsp. peanut oil
1 can pineapple chunks in syrup
1/4 c. white vinegar
3 tbsp. tomato sauce
1 c. water

Trim pork, discarding fat (and bones if any). Cut pork into 1 inch pieces. Mix soy sauce, 1 1/2 tablespoons water, sugar and egg yolk in large glass bowl. Mix in pork. Cover and let stand 1 hour, stirring occasionally.

Drain pork, reserving soy sauce mixture. Coat pork with 8 tablespoons of the cornstarch. Heat the 3 cups oil in wok or deep fryer over high heat until it reaches 375 degrees. Cook 1/2 of the pork in oil until brown, about 5 minutes. Drain on absorbent paper. Cook and drain remaining pork.

Cut yellow onion into thin slices. Cut green onion into thin diagonal slices. Remove seeds from pepper and chop coarsely. Clean mushrooms and cut into halves or quarters. Cut celery into 1/2 inch diagonal slices. Cut zucchini lengthwise into quarters and then into 1/4 inch wide pieces.

Heat the 3 tablespoons peanut oil in wok over high heat. Add all the prepared vegetables to oil. Stir fry 3 minutes. Drain pineapple, reserving syrup. Add the syrup, reserved soy sauce mixture, vinegar and tomato sauce to vegetables. Combine water and remaining 2 tablespoons cornstarch. Add to vegetables. Cook and stir until sauce boils and thickens. Add pork and pineapple. Cook and stir until hot throughout.