In a large skillet, I use 12" skillet, pour enough olive oil to coat the bottom of the pan. Sweat the garlic and onion together, do not burn the garlic, it will become too nutty. Once the garlic and onion is cooked down, the onion is tranparent, remove from the oil and place in a 9X13 pan. I usually take the ground pepper and salt and mix them together so that coating the pork is easier. Take the pork out of the vacume sealed bag, rinse and pat dry. Take the salt and pepper and pat onto the pork, sear on all sides. After searing on all sides, place in the 9X13 pan on top of the garlic and onions. Deglaze the pan with the balsamic vinegar, reduce and then pour over the pork, onions, and garlic. Place in middle rack for about 20-25 minutes until middle of pork is about medium well to well done.
When serving, I slice the pork and then take the glaze and onion/garlic mixture and pour over the pork. It's delicious -- ENJOY.