Can be prepared in 45 minutes or less.

Ingredients

　　4 tablespoons olive oil

　　two 1-inch-thick tuna steaks

　　5 Kalamata or other brine-cured black olives, pitted

　　2 teaspoons drained bottled capers

　　1 garlic clove, minced

　　1 teaspoon Dijon-style mustard

　　2 teaspoons balsamic vinegar, or to taste

　　1 plum tomato, seeded and chopped

　　1 tablespoon water

　　2 tablespoons finely chopped drained bottled roasted red peppers plus additional for garnish if desired

　　1 tablespoon finely chopped white and green parts of scallion plus additional for garnish if desired

　　lemon wedges as an accompaniment

　　In a heavy skillet, preferably non-stick, heat 1 tablespoon of the oil over moderately high heat until it is hot but not smoking and in it sautée the tuna steaks, patted dry and seasoned with salt and pepper, for 4 to 5 minutes on each side, or until they are just cooked through. While the tuna is cooking, in a blender or small food processor blend together the olives, the capers, the garlic, the mustard, the vinegar, the tomato, the water, and salt and pepper to taste and with the motor running add the remaining 3 tablespoons oil, blending the dressing until it is emulsified. Transfer the tuna to plates and wipe the skillet clean. Pour the dressing into the skillet, heat it over moderate heat until it is hot, and stir in 2 tablespoons of the roasted peppers and 1 tablespoon of the scallion. Spoon the dressing over the tuna, garnish the tuna with the additional roasted peppers and scallion, and serve it with the lemon wedges.