Heat charcoal grill until coals are white-hot, 30 to 40 minutes. Combine all ingredients, except fish and salsa, in a small mixing bowl. Rub mixture generously over steaks.Grill steaks over medium fire, 5 to 7 minutes per side; sear crosshatched grill marks on each side by turning steaks ninety degrees halfway through cooking time. Check for doneness; steaks should be opaque in center. Top with salsa, and serve immediately.