Prepare the Chicken Brine: In a bowl, combine the buttermilk, paprika, garlic powder, salt, and black pepper. Add chicken thighs and coat them well. Cover and let marinate in the fridge for at least 1 hour or overnight for more flavor.
Bread the Chicken: In a separate bowl, mix flour, cornstarch, paprika, garlic powder, onion powder, cayenne pepper, salt, and pepper. Take each piece of marinated chicken and coat it in the flour mixture, pressing down to ensure it sticks.
In a large skillet, heat oil over medium-high heat to fry the chicken. Fry each breaded chicken thigh until golden brown and crispy, about 4-5 minutes per side. Place the food on a paper towel to drain off any excess oil.
Assemble the Burger: Spread mayo or sauce on the bottom half of each burger bun. Layer with lettuce, fried chicken, cheese, tomato, and pickles. Top with the other half of the bun.
Serve and Enjoy: Serve hot with your favorite side of fries or coleslaw.