Season the pork with salt and black pepper. Heat the oil and butter in a large frying pan over a medium-high heat. When the butter is foaming, cook the pork chops for 7-9 minutes, until cooked through and brown on both sides.
Remove the chops from the pan, cover with aluminium foil and rest for 10 minutes.
Meanwhile, drain all but most of the fat from the frying pan and heat over a low heat. Cook the garlic and onion for 2-3 minutes.
Increase the heat and add the wine. Bring to a boil and simmer for 3 minutes until it has reduced by half.
Stir in the chicken stock and Avonmore Cooking Cream, and simmer for eight minutes until thickened.
Stir in the mustard and sage leaves. Serve over the pork chops.