01 - Place chicken pieces in a bowl and submerge in pickle brine and hot sauce. Cover tightly and refrigerate for at least 2 hours, or overnight for maximum flavor penetration.
02 - In a large bowl, whisk together the flour, cornstarch, garlic powder, onion powder, smoked paprika, kosher salt, and black pepper until evenly combined.
03 - Remove chicken from the brine and discard the used brine. Pat each piece thoroughly dry with paper towels, then coat completely in the seasoned flour mixture, pressing firmly to adhere.
04 - Heat oil in a deep skillet or heavy-bottomed pot to 350°F. Working in batches to avoid crowding, fry chicken pieces for 4 to 6 minutes per side until golden brown and cooked through to an internal temperature of 165°F. Drain on paper towels.
05 - In a small bowl, stir together the mayonnaise and Dijon mustard until smooth and well blended.
06 - Spread the mayonnaise-mustard sauce on both halves of each slider bun. Layer a lettuce half, a fried chicken piece, and a dill pickle slice on the bottom bun, then cap with the top half. Serve immediately while hot and crispy.