Chicken and Waffle Sandwiches

1. In a 9-by-13-inch baking dish, combine the buttermilk and hot sauce. Add the chicken breasts and toss to coat. Marinate for at least 1 hour in the refrigerator (and up to overnight).

2. In a large, shallow bowl, whisk the flour with the salt, pepper, baking powder and cayenne to combine.

3. In a large sauté pan, heat 2 inches of oil over medium heat until it reads 350°F on a thermometer. While the oil heats, remove each chicken breast from the buttermilk and shake off the excess. Dredge the chicken in the flour to coat well. Dip the chicken back into the buttermilk and then back into the flour mixture.

4. When the oil is very hot (test it by dropping in a piece of extra breading--it should sizzle and immediately float to the surface), add the chicken and cook until golden brown, 3 to 5 minutes per side. Transfer the chickenfrom the oil to a plate lined with absorbent paper towels; let drain.

5. To build the sandwiches, place a waffle on a plate. Top it with ¼ cup arugula and 1 or 2 tomato slices. Top with a piece of chicken and another waffle. Serve immediately.