This Mediterranean-inspired relish pairs nicely with most grilled fish, so if tuna isn't your favorite, substitute salmon, halibut, or swordfish steaks. For a shortcut, pulse the tomatoes and olives a few times in a food processor and then add the remaining ingredients and pulse to combine.
Make the relish:
Combine all the ingredients, seasoning with salt and pepper to taste. (The saltiness of the ingredients in this relish will vary, so make sure to taste before seasoning.)
Grill the tuna:
Clean and oil the grates on a gas grill and heat the grill to medium high, or prepare a medium-hot charcoal fire.
Meanwhile, generously coat both sides of the tuna with the oil and season both sides with salt. Let the tuna sit at room temperature for 15 minutes (while the grill heats). Grill the tuna steaks directly over the heat source (covered on a gas grill, uncovered on a charcoal grill), without touching, until they have good grill marks, 2 to 4 minutes. Flip the steaks and grill until the second sides have good grill marks and the fish is done to your liking, another 2 to 4 minutes. (Check for doneness by slicing into one of the thicker pieces.) Serve immediately, topped with the relish.
Make Ahead Tips
You can make the relish up to 2 days ahead, which will allow the flavors to marry.
nutrition information (per serving):
based on six servings;
Photo: Scott Phillips