You could also bake the tuna.

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Daily Dish | The South Beach Diet
Grilled Tuna With Teriyaki Glaze

2 servings

Ingredients

2 tablespoons light soy sauce
1 1/2 tablespoons dry sherry or chicken broth
1/2 tablespoon fresh ginger, grated
1 1/2 cloves garlic, minced
2 tuna steaks (5 ounces each)
1/2 large mango, peeled and cut into spears
1/2 red bell pepper, quartered lengthwise

Instructions
In a small bowl, combine the soy sauce, sherry or broth, ginger, and garlic. Divide the marinade into 2 medium, shallow bowls. Place the tuna in one bowl and the mango and bell pepper in the other. Turn the tuna, mango, and bell pepper to coat both sides. Cover and refrigerate for 15 minutes.

Coat a grill rack or broiler pan rack with cooking spray. Preheat the grill or broiler to medium.

Place the tuna, mango, and bell pepper on the prepared rack or pan. Discard the marinade from the tuna bowl. Grill or broil, basting occasionally with the marinade from the mango bowl, for 4 minutes per side or until the tuna is just opaque and the mango and bell pepper are heated through and glazed.

Nutritional Information:
207 calories
2 g total fat (1 g sat)
67 mg cholesterol
12 g carbohydrate
33 g protein
2 g fiber
509 mg sodium