By Mayo Clinic Staff

Dietitian's tip:

For the tastiest tacos, be sure the swordfish is fresh, not frozen, and try to use freshly made corn tortillas.

Note: The Food and Drug Administration recommends that women who might become pregnant, pregnant women, nursing mothers and children younger than age 5 should avoid eating swordfish because they may contain high levels of mercury and other toxins. Substitutes for swordfish include halibut, mahi-mahi, sea bass, cod, snapper or other firm-textured fish.

Number of servings

Serves 6


  1. 3/4 cup pitted black olives, chopped
  2. 2 tomatoes, seeded and diced, plus 1/2 cup chopped
  3. 3 green (spring) onions, thinly sliced
  4. 1/2 jalapeno chili, seeded and minced (optional)
  5. 4 tablespoons fresh lime juice
  6. 1 teaspoon grated lime zest
  7. 1 tablespoon rice vinegar
  8. 3 tablespoons extra-virgin olive oil
  9. 4 tablespoons chopped fresh cilantro (fresh coriander)
  10. 1/2 teaspoon salt
  11. 1/4 teaspoon pepper
  12. 1 small head romaine (cos) lettuce, thinly sliced (about 3 cups)
  13. 1 cup coarsely grated radishes
  14. 1/2 roasted and seeded red bell pepper (capsicum)
  15. 1 teaspoon chili powder
  16. 1 teaspoon ground cumin
  17. 12 small corn tortillas
  18. 1 3/4 pounds swordfish steaks or fillets, cut into 1-inch cubes


In a bowl, combine the olives, diced tomatoes, green onions, jalapeno (if using), 2 tablespoons of the lime juice, the lime zest, vinegar, 2 tablespoons of the olive oil, 2 tablespoons of the cilantro, the salt and pepper. Toss gently until all the ingredients are evenly distributed. Cover and refrigerate until ready to use. Place the romaine and radishes in separate bowls, cover and refrigerate until ready to use.

Cut the roasted bell pepper half into chunks. In a blender or food processor, combine the roasted pepper, 1/2 cup chopped tomato, 1/4 teaspoon of the chili powder, 1/4 teaspoon of the cumin and the remaining 2 tablespoons lime juice. Pulse to puree. Stir in the remaining 2 tablespoons cilantro and set aside.

Preheat the oven to 300 F. Wrap the tortillas in aluminum foil and warm in the oven for about 10 minutes. Remove from the oven and keep warm.

Raise the oven temperature to 400 F. In a bowl, toss the swordfish cubes with the remaining 1 tablespoon olive oil, 3/4 teaspoon chili powder and 3/4 teaspoon cumin. Arrange the fish in a single layer on a baking sheet and bake until the fish is opaque throughout when tested with the tip of a knife, about 5 minutes.

To serve, place 2 tortillas on each individual plate. Divide the tomato-olive mixture evenly among the tortillas and top with equal portions of the fish. Add some lettuce and radishes to each and drizzle with lime-cilantro sauce. Serve immediately.

Nutritional analysis per serving

Serving size :2 tacos

  • Total fat 16 g
  • Calories 403
  • Protein 33 g
  • Cholesterol 55 mg
  • Total carbohydrate 33 g
  • Dietary fiber 5 g
  • Monounsaturated fat 9 g
  • Saturated fat 3 g
  • Sodium 387 mg

This recipe is one of 150 recipes collected in "The New Mayo Clinic Cookbook," published by Mayo Clinic Health Information and Oxmoor House, and winner of the 2005 James Beard award.

April 15, 2011