1. Stir together beef broth, soy sauce, cornstarch, cocoa, garlic, ginger and red pepper flakes; set aside. Cut beef steak into 1/4-inch wide strips.
2. Heat large skillet or wok over high heat about 1 minute or until hot. Drizzle about 1 tablespoon oil into pan; heat about 30 seconds. Add beef strips; stir-fry until well browned. Remove from heat; set aside.
3. Drizzle remaining 2 tablespoons oil into pan; add onion pieces and carrots. Stir-fry until onion is crisp, but tender. Add broccoli and red pepper strips; cook until crisp-tender.
4. Return beef to pan; add broth mixture. Cook and stir until mixture comes to a boil and thickens. Serve over hot rice with additional soy sauce and cashew pieces, if desired. 4 to 6 servings.