The key to slow-cooked pork is choosing the right cut: thick-cut bone-in shoulder blade chops. This cut comes from closer to the shoulder, where the muscles are tougher and have more connective tissue, making them ideal for slow, moist heat. The bone helps to slow moisture loss, keeping the meat from drying out like other types of pork chops. Shoulder blade chops are often sold as pork shoulder blade steaks. They don’t look like a classic oblong, meaty pork chop. Shoulder blade chops are almost rectangular in shape, with a mosaic of white and dark meat and a bone running through the middle. The second secret to great slow-cooked pork chops is to brine the meat before it goes into the slow cooker, for maximum flavor and to also prevent the chops from drying out. We add mustard seeds and a bay leaf to our brine mixture, but you can also use a standard salt and sugar brine. This recipe is a great base for many flavorful pork chop dinner recipes.
Combine first 4 ingredients and 1⁄3 cup of the salt in a large bowl; whisk until salt and sugar dissolve. Add pork chops, submerging completely; cover and chill 1 1⁄2 hours. Remove from brine; discard brine. Pat dry, and sprinkle with pepper and remaining 1 1⁄2 teaspoons salt.
Heat oil in a large skillet over medium-high. Cook pork chops until browned, 3 to 4 minutes per side. Remove from skillet. Add onions; cook, stirring occasionally, until softened, about 6 minutes. Add apple cider. Cook until reduced slightly, 2 minutes. Transfer onion mixture to a 6-quart slow cooker; stir in broth and mustard. Place pork chops on top of onion mixture. Cover; cook on LOW until pork is tender, 4 hours.