Cut the fish into 4 uniformly sized pieces, season both sides with salt and pepper and set aside.
Make the Mojo Mayo by whisking together the garlic, onion, orange juice, lemon juice, lime juice, cumin, oregano, salt and pepper in a small bowl. Reserve 1/4 cup of this mixture and whisk the mayonnaise into the remainder. Set aside.
Heat the oil in a large skillet over high heat. Add the fish in a single layer and cook until lightly browned, about 1-1/2 minutes. Turn the pieces carefully and brown on the other side, 1-1/2 minutes more. Pour the reserved mojo mixture over the fish, turn again, and continue cooking until the fish is opaque throughout, an additional 2 to 3 minutes.
To serve, line each roll with romaine lettuce leaves, add a tomato slice and a piece of fish and top with the Mojo Mayo.
Tips for Making This Recipe
If fresh grouper is not available in your area, halibut and cod can be substituted.Serve with a corn salad: Combine cooked corn with a tiny amount of oil, some lime juice, a handful of chopped, fresh cilantro, and salt and pepper to taste.
About the Mojo:
Cuban Mojo is a marinade that is traditionally made with sour orange juice (or a combination of orange, lemon and lime juices), garlic, and spices. Try using the same proportions we list in our recipe, minus the mayonnaise, for a delicious marinade for chicken or pork.