Chicken frying isn’t just for steak. This Southern tradition of shallow pan frying thinly pounded cuts of meat coated in seasoned flour (as opposed to deep frying whole pieces) works just as well with chicken or pork. Here chicken breasts are dipped in buttermilk, then dredged in flour seasoned with paprika, black pepper, and ground mustard, plus a little powdered sugar to help with browning. They’re fried until crispy, put in a hoagie roll smeared with mayonnaise, and topped with shredded iceberg lettuce and quick-pickled sweet peppers. Make the pickled peppers and some classic macaroni salad in advance and you’ll have a patio-friendly dinner on the table in about 40 minutes.
Game plan: The pickled peppers need to be made at least 1 day in advance, so plan accordingly. Any leftover peppers can be stored in the refrigerator for up to 1 month.
Using a paring knife, make 3 to 4 (1/2-inch) vertical slits in each pepper. Pack the peppers and bay leaf tightly in a 1-quart jar, leaving about 1/2 inch of room at the top of the jar.
Make the brine: Toast the mustard seeds and peppercorns in a small saucepan over medium heat until fragrant, about 2 minutes. Add the vinegar, water, sugar, and salt, whisk to dissolve the sugar and salt, and bring to a rapid simmer.
Immediately pour the brine over the peppers, making sure to cover them completely (not all of the brine will fit in the jar). Place the remaining brine in a small heatproof container. Let the peppers and the reserved brine cool to room temperature, about 1 hour.
Cover the jar of peppers and the container of reserved brine with tightfitting lids. Shake the jar of peppers or turn it upside down to evenly distribute the brine and spices, then place it in the refrigerator for at least 1 day and preferably 1 week before using. Store the reserved brine in the refrigerator. Check the brine level in the jar periodically to make sure the peppers are completely submerged, topping it off as necessary with the reserved brine. When the peppers are ready, make the sandwich. (The pickled peppers can be kept in the refrigerator for up to 1 month.)
For the chicken:
Place the buttermilk in a large, shallow dish; set aside. Combine the flour, sugar, measured salt, paprika, measured pepper, baking powder, and ground mustard in another large, shallow dish and whisk to combine; set aside.
Cut each chicken breast in half horizontally. Place 1 piece between 2 sheets of plastic wrap or in a resealable plastic bag and pound to an even thickness (about 1/4 to 1/2 inch thick) with a meat pounder or the bottom of a pan; set aside. Repeat with the remaining pieces of chicken. Season the chicken generously on both sides with salt and pepper.
To bread the chicken, dip 1 piece in the buttermilk and let the excess drip off. Dredge in the flour mixture and shake off any excess. Set the coated chicken on a baking sheet and repeat with the remaining pieces.
Heat the oil in a large frying pan over medium-high heat until shimmering but not smoking (about 350°F on a deep-frying/candy thermometer). Meanwhile, fit a wire rack over a second baking sheet; set aside.
When the oil is ready, add 2 pieces of the chicken and fry until golden brown and cooked through, about 2 minutes per side. Remove to the wire rack and season with salt. Repeat with the remaining chicken. Cover the fried chicken loosely with a piece of aluminum foil; set aside.
To serve, stem and thinly slice the pickled peppers. Evenly divide the mayonnaise among the rolls, spreading it all over both of the cut sides. Place the chicken pieces on the rolls, top with the lettuce and peppers, and serve immediately.