Trim the excess fat from the outside of the steaks (this will help prevent flare-ups on the grill). Crush or coarsely grind the cumin seeds and mix with red pepper and salt. Sprinkle each side of each sirloin chop evenly and pat the mixture in so it sticks. Refrigerate 1-3 hours.
Combine tomato, cucumber, lemon juice, oil and salt and let sit while you cook the chops:
Preheat a grill to very hot (450-500ºF). Place chops on the grill and cook uncovered 7 minutes. Turn and cook another 5-7 minutes until the internal temperature reaches 155ºF for medium and 160ºF for medium-well.
Add herbs to tomato salad, stir, and serve with chops.