Place the jalapeno peppers on grill over medium, ash-covered coals. Grill uncovered, for about 11 to 13 minutes or until evenly blistered and blackened. Place in a food-safe plastic bag; close bag. Let stand 10 to 15 minutes until skins are loosened.
Press black pepper and salt evenly onto beef steaks. Place steaks on grill over medium, ash-covered coals. Grill, uncovered, 10 to 12 minutes for medium rare to medium doneness, turning occasionally (7 to 10 minutes for medium-rare to medium doneness). Remove from grill and let stand while preparing vinaigrette.
Meanwhile prepare Jalapeno Vinaigrette:
Remove and discard skins, seeds and membranes from jalapeno peppers. Place peppers, lime juice, cilantro, water and salt in food processor container. Cover and pulse on and off until combined. With motor running, slowly add oil through opening in cover, processing until well blended.
Arrange salad greens on serving platter. Fan the mango and avocado slices over greens.
Carve steaks into slices and season with salt, to taste. Arrange over salad. Top with shallots and drizzle with vinaigrette. Sprinkle with cheese.