Reserve 2 tablespoons flour and set aside, place the remaining flour in a shallow dish.
To the bowl mix together the Cajun seasoning, garlic powder and black pepper.
Rub the pork chops all over with the seasoning.
Place the buttermilk in a shallow bowl.
Dip the chops in buttermilk, then dredge in flour.
Heat oil and butter in a skillet, then brown the chops over medium high heat for about 5 minutes per side or until golden brown and cooked through; remove to a plate, cover loosley with foil to keep warm(do not drain the fat in the pan).
Add in chopped onion and saute until soft (about 3-4 minutes, you might need to add in more butter if needed to the pan).
Add in the reserved 2 tablespoon flour to the skillet, then stir/whisk in the milk and seasoned salt; whisk or stir constantly until thickened and bubbly.