Heat oven to 425°F. Place bell peppers on metal baking sheet; spray with nonstick cooking spray. Set aside.
Press 1 teaspoon paprika evenly onto all surfaces of beef roast. Place roast on rack in shallow roasting pan. Do not add water or cover. Roast in 425°F oven 30 to 40 minutes for medium rare; 40 to 50 minutes for medium doneness. Roast bell peppers in oven with beef about 30 minutes or until tender. Set peppers aside to cool.
Remove roast when instant-read thermometer registers 135°F for medium rare; 150°F for medium. Transfer roast to carving board; tent loosely with aluminum foil. Let stand 20-25 minutes. (Temperature will continue to rise about 10°F to reach 145°F for medium rare; 160°F for medium.)
Meanwhile, cook barley according to package directions. Set aside to cool slightly.
Cut beef into 1/2 inch pieces; season with salt and black pepper. Whisk lime juice, oil and 1/2 teaspoon paprika in small bowl until blended. Toss with beef, barley, roasted peppers, mangoes, green onions and cilantro in large bowl. Serve in Boston lettuce leaves, if desired.
Recipe and photo as seen in The Healthy Beef Cookbook, published by Houghton Mifflin Harcourt
Nutrition information per serving: 309 Calories; 81 kcal Calories from fat; 9 g Total Fat; 3 g Saturated Fat; 4 g Monounsaturated Fat; 60 mg Cholesterol; 246 mg Sodium; 35 g Total Carbohydrate; 4.3 g Dietary Fiber; 26 g Protein; 2.3 mg Iron; 8.4 mg Niacin; 0.8 mg Vitamin B6; 1.3 mcg Vitamin B12; 4.7 mg Zinc; 27 mcg Selenium;