Tuna in a Tomato

6 large tomatoes3 cans (6 ounces each) tuna, drained3 tablespoons capers, roughly chopped1 cup fresh flat-leaf parsley leaves, roughly choppedZest of 1 lemon 1/4 cup fresh lemon juice1 tablespoon extra-virgin olive oil 1/4 teaspoon black pepperWith a paring knife, cut out and discard the stem of each tomato. Using a spoon, hollow out the tomatoes, leaving each with a 1/4-inch shell, and transfer the pulp to a medium bowl.Add the remaining ingredients to the tomato pulp and toss gently. Spoon the mixture back into the tomatoes and serve.Serves six.Cook's note: Next time, try basil in place of parsley, substitute chopped olives for capers, add finely chopped red onion or scallions, opt for equal amounts of mayonnaise and sour cream in place of the olive oil, stir in a couple of spoonfuls of cooked rice.Nutrition values per serving: 265 calories, 10 g fat (2 g saturated), 10 g carbohydrates, 3 g fiber, 27 g protein, 15 mg cholesterol, 482 mg sodium."Real Simple: Meals Made Easy" (2006 Time Inc., $24.95)