Partially freeze meat. Then, thinly slice meat across the grain into bite-size strips.
Prepare Orange Sauce; set aside.
Spray a wok or 12-inch skillet with nonstick spray coating. Heat over medium-high heat. Stir-fry onions and garlic for 1 minute; remove from wok. If necessary, add 1 tablespoon oil. Stir-fry meat for 2 to 3 minutes or till done. Push meat away from center of wok.
Stir Orange Sauce and pour into the center of wok. Cook and stir till thickened and bubbly. Stir in spinach, water chestnuts, and onion mixture. Cover and cook for 1 minute. Serve over rice.
Orange Sauce: In a small bowl stir together 1 tablespoon cornstarch, 1 teaspoon sugar, and 1 teaspoon instant beef bouillon granules. Stir in 1 teaspoon finely shredded orange peel, Ω cup orange juice, and 1 tablespoon soy sauce.
Makes 4 servings.
*Note: You may need to cook the beef in the oil to keep it from sticking to the wok. If you do, add 25 calories to the calorie count of each serving.