Prepare the apples: core and slice the apple into 1/4- inch pieces. (I left the skin on to add more color to the dish). Melt the butter over medium-high heat and cook the apples for about 5-6 minutes until softened but not floppy. Turn the apples occasionally in the pan. Transfer to a bowl.

Season both sides of the pork chops with salt and pepper. Add the oil to the same pan and turn the heat up to medium-high. Cook the pork chops about three minutes each side or until surface turns golden brown. Transfer to a bowl and cover with foil.

In the same pan, sauté the red onion slices until softened. Over medium-high heat, add the Calvados (or brandy) and stir, then add the hard cider and continue to stir for several more minutes. Periodically scrape the bottom of the pan (deglaze) in order to incorporate the golden bits into the sauce. Add several tsps. of dried rosemary (if using), thickened cream, Dijon mustard, and salt/pepper. Cook for 5-10 minutes until the sauce reduces slightly and the flavors infuse.

Add the apples and pork chops (including any juices) to the sauce. Cover the pan and let cook for several minutes to warm the pork through. Serve with mashed potatoes and decorate the dish with a sprig of rosemary.