Five-Grain Turkey BLTs with Heirlooms and Arugula

1 teaspoon vegetable oil8 slices (8 ounces) thick-sliced turkey bacon (see note)8 slices (4 ounces) five-grain loaf bread4 thick slices ripe heirloom tomato (see note)4 teaspoons reduced-fat mayonnaise4 ounces prewashed arugula leaves, or to tasteSalt and pepper, to tasteHeat the oil in a large (preferably 14-inch, see note) nonstick skillet over medium-high heat. Arrange the bacon in the skillet, and cook until very crisp on both sides, about 10-15 minutes, depending on bacon's thickness. Turn frequently and remove to a plate lined with paper towels when done. (If the bacon sticks to the skillet, use a spatula to loosen it from the pan and add more oil if necessary.)While the bacon cooks, lightly toast the bread slices in a toaster or toaster oven, and then set aside. Cut the tomato slices; set aside.Assemble the sandwiches: Spread a 1/2 teaspoon mayo for each sandwich, and layer each with tomato, arugula and bacon, cut to fit if necessary. Salt and pepper to taste. Cut sandwiches in half, if desired, and serve.Serves four.Cook's notes: For testing, we used Applegate Farms Turkey Bacon, and each thick slice is 1 ounce. Other brands can be used, but the slices may be thinner and cook faster. Pork bacon also can be used. Heirloom tomatoes usually are available at farmers' markets, in specialty groceries and most large supermarkets. Any variety of ripe tomatoes can be used.If your skillet is not large enough to hold all of the bacon without overlapping slices, cook it in batches.The size of this recipe is flexible, and you can make one sandwich at a time or as many as you need. Any extra turkey bacon can be refrigerated in a zipper-top bag for three days or frozen for up to one month.@Recipe nutrition:Nutrition values per serving: 231 calories (26 percent from fat), 7 g fat (1 g saturated), 28 g carbohydrates, 5 g fiber, 20 g protein, 50 mg cholesterol, 685 mg sodium.