Add chicken, buttermilk, hot sauce, and 1 teaspoon kosher salt to a large resealable bag and refrigerate at least 4 hours or up to overnight.
Heat 1 ½ inches of canola oil in a dutch oven or large pot to 350 degrees.
In a wide bowl, combine flour, remaining salt, pepper, garlic powder, smoked paprika, and canola oil. Remove the chicken from the buttermilk marinade and dip each piece in the flour mixture until well coated.
Fry two piece of chicken at a time until golden brown and cooked through, about 4 minutes per side. Rest the cooked chicken on paper towels to cool.
Make the sauce by combining all sauce ingredients in a small bowl.
Assemble sandwiches by spreading the open sides of the toasted buns with sauce. Top the bottom bun with fried chicken, pickles, lettuce, and the top bun.
Nutritional values are based on one of four sandwiches.