Heat oil in a wide frying pan over high heat; add onion, carrots, and garlic and cook stirring for about 3 minutes or until vegetables are crisp-tender. Add green pepper and cook for 1 minute. Add pineapple, tomatoes, and soybeans and cook for 2 minutes or until hot. Stir sweet-sour sauce, pour into pan, and continue to cook, stirring, until sauce bubbles and thickens. Per serving: 10 grams protein, 72 grams carbohydrate, no cholesterol, 391 calories