Whisk the buttermilk and the hot sauce together in a nonreactive bowl. Marinate the chicken pieces in mixture and refrigerate overnight.
Preheat oven to 400°F. Remove each piece of chicken to a baking rack set over a sheet pan to catch excess marinade. Discard remaining marinade in bowl. In a separate shallow dish, combine the bread crumbs, flour, seeds, and seasonings. Coat each piece of chicken in bread crumb mixture and transfer to a baking sheet lined with foil in a single layer; pieces should not touch each other. Discard remaining breading. Spray the chicken with the cooking spray. Bake until the breading is crispy and golden, 40-45 minutes. If the breading begins to darken before chicken is fully cooked, cover pan loosely with foil. Chicken is done when an inserted meat thermometer reaches 165°F, no pink remains inside, or when juice from the center runs clear.
