Combine mustard, peppercorns and cumin in small bowl. Remove and reserve 1/2 for brushing. Spread remaining mustard mixture on both sides of beef Sirloin Tip Center Steaks. Cover and marinate in refrigerator 1 hour.
Combine butter, cilantro and garlic in small bowl. Set aside.
Place steaks and peppers on grid over medium, ash-covered coals. Grill, covered, 8 to 9 minutes (over medium heat on preheated gas grill 8 to 11 minutes) until steaks are medium rare (145°F) doneness and peppers are blackened, turning occasionally and brushing steaks with reserved mustard mixture during the last 4 minutes. (Do not overcook.)
Remove blackened peppers; cover and let stand 5 minutes. Remove skin, stems and seeds. Chop peppers and stir 1/2 into butter mixture. Top each steak with 1 teaspoon butter mixture. Sprinkle with remaining chopped peppers. Serve with remaining butter.
Nutrition information per serving: 278 Calories; 9 Calories from fat; 1g Total Fat ) 108 mg Cholesterol; 581 mg Sodium; 9 g Total Carbohydrate; 37 g Protein; 5.5 mg Iron; 5 mg NE Niacin; 0.6 mg Vitamin B6; 3.7 mcg Vitamin B12; 9.2 mg Zinc.
This recipe is an excellent source of Protein, Iron, Niacin, Vitamin B6, Vitamin B12, and Zinc.