Assemble the water bath and heat the water using your sous vide device to 140F. Tip: begin by using warm/hot water from your tap so that the water bath heats to 140F quicker. Make sure the water is between the min/max line on the sous vide device. Set the timer to 1 hr and 15 minutes.
Season both sides of your pork chops with salt and pepper. Then add the garlic and rosemary to both sides. Place both pork chops in a largish resealable/vacuum bag along with ½ cup of apple juice. If using vacuum seal, then remove as much air from the bag as possible. If using resealable, remove as much air from the bag using the water immersion method (when it's time to add the bags to the heated water bath). From anovaculinary.com: "Place the food in a zipper lock bag and slowly lower the bagged food into a bowl of water, letting the pressure of the water press air through the top of the bag. Once most of the air is out of the bag, carefully seal it just above the water line."
Once the temperature reaches 140F, place the vacuum sealed bag with the pork chops in the water bath, or add the resealable bag using the water immersion method described above. Allow to cook for 1 hr and 15 minutes.
After 1 hr and 15 minutes, remove the bag from the water bath and the pork chops from the bag (reserve the juices in the bag). Heat up the olive oil in a skillet or cast iron pan on high, and quickly sear both sides of the pork chops until you get a nice color (around 45 sec to 1 min on each side). Set aside.
Lower the heat to medium high, and then pour the juices from the bag into the skillet or cast iron pan. Add the dark brown sugar and ½ cup of apple juice. Stir frequently until you get a lovely caramelized sauce!
Pour the caramelized sauce over your juicy and delicious pork chops and serve with heaps of fluffy mashed potatoes!