Coat an outdoor grill or stove-top grill pan with cooking spray and preheat to medium-high.
Skewer steak and zucchini on separate skewers. Set aside. In a small bowl, whisk together black bean sauce, rice wine vinegar, and sesame oil. Brush mixture all over beef and zucchini. Place skewers on hot grill. Grill skewers for 5 minutes, turning once during cooking. Sprinkle sesame seeds all over skewers and grill 2 more minutes, until steak is cooked through and seeds are golden brown.
Meanwhile, cook rice according to package directions, adding bell pepper at the beginning of cooking time. Season rice, to taste, with salt and black pepper. Serve half of the beef skewers and all of the zucchini skewers over rice. Save remaining beef skewers for another meal.
If you are using wooden skewers, soak them in water for 1 hour before using.