Sicilian Tuna Steak

Ingredients

• 1 pound fresh tuna steaks, 1 inch thick
• 1 small onion, chopped
• 2 cloves garlic, minced
• 1 tablespoon extra-virgin olive oil
• 2 pounds roma tomatoes, seeded and chopped, or one 28-ounce can diced tomatoes, drained
• 1/2 cup dry white wine
• 1/4 to 1/2 teaspoon crushed red pepper
• 1/4 cup pitted ripe olives
• 2 tablespoons capers, rinsed and drained
• 2 tablespoons chopped fresh basil or 2 teaspoons dried basil, crushed
• 1/4 teaspoon kosher salt
• 1/8 teaspoon freshly ground black pepper
• 1 tablespoon lemon juice