In a shallow dish, whisk together the flour, Panko breadcrumbs, seasoned salt, onion powder, garlic powder, and paprika. Set aside. In another shallow dish, whisk together the whole milk, vinegar, and egg.
Place the breaded chicken onto a plate in a single layer. Refrigerate uncovered to let the breading set. Add the cooking oil over medium heat to a large frying pan. Brown the chicken then turn them over carefully. Place cooked chicken onto a rack over a baking sheet and into the oven.
In the pan add the flour to the drippings stirring constantly over medium-high heat. Scrape any brown bits from the bottom of the skillet. Add the salt and fresh cracked black pepper.
Gradually add the evaporated and whole milk whisking constantly. Turn the heat up to medium-high and bring to a boil. Lower the heat and allow the gravy to gently simmer.