Partially freeze meat. Thinly slice across the grain into bite-size strips. Set aside.
Cook sliced potatoes in boiling water about 5 minutes or until tender. Drain and set aside.
Meanwhile, for sauce, stir together beef broth, cornstarch, and salt.
Spray a wok or large skillet with nonstick spray coating. Heat over medium-high heat. Add onion and stir-fry 2 minutes. Add green pepper and stir-fry about 2 minutes more or until vegetables are crisp-tender. Remove from wok.
Add oil to hot wok. Add beef and curry powder. Stir-fry 2 to 3 minutes or until beef is done. Push beef from center of wok.
Stir sauce and add to center of wok. Cook and stir until thickened and bubbly. Stir in onion mixture, potatoes, and tomato. Cook and stir all ingredients for 1 minute or until heated through. Makes 4 servings.