Chicken maryland with milk gravy

Ingredients

• 8 chicken pieces
• 1 cup buttermilk
• 1 1/2 cup flour, sifted
• 1 teaspoon smoked paprika
• 1 teaspoon celery salt
• 1 teaspoon dried oregano
• freshly ground black pepper to taste
• 2 tablespoons oil
• 30 grams butter
• 1/2 small onion, peeled and chopped
• 2 tablespoons flour, extra
• 1/2 cup hot milk
• ½-¾ cup hot chicken stock
• salt and freshly ground black pepper to taste