Arrange potatoes and onions on the bottom of your slow cooker.
Season with salt and pepper and add ½ tablespoon olive oil; stir to combine. Set aside.
Heat half tablespoon olive oil in a nonstick skillet over medium-high heat.
Season pork chops with salt and pepper and add to skillet; sear until just browned on both sides.
Transfer pork to slow cooker and arrange over potatoes; set aside.
In a small mixing bowl, combine olive oil, wine, mustard, garlic, rosemary, and thyme; whisk until well combined.
Pour sauce over pork chops.
Cover and cook on LOW for 5 to 6 hours, or on HIGH for 3 hours, just until pork chops reach an internal temperature of 165F and potatoes are thoroughly cooked.
Remove from slow cooker.
Garnish with parsley and serve with additional mustard.