In a large bowl, add pork shoulder, 2 teaspoons oil, salt, and pepper, rubbing meat to coat well. Let stand for 5 minutes.
In a large skillet, heat remaining 2 tablespoons oil over medium-high heat. Sear roast until crisp and browned, 3 to 4 minutes per side.
In a 6-quart slow cooker, place stock, onions, parsley, rosemary, garlic, and pork. Cook on low for 8 hours. Pork will be fork tender and easily pull away from bone. Discard rosemary sprigs. Using two forks, shred pork and stir to combine with cooking liquid. Serve with Pickled Grapes. Garnish with rosemary, if desired.
Pickled Grapes
Add grapes, mint, ginger, and mustard seeds to a 1-quart glass jar with lid.
In a medium saucepan, bring vinegar, 1 cup water, sugar, and lemon zest and juice to a boil over medium-high heat. Pour mixture into jar, covering grapes. Place lid on jar and let stand upside down at room temperature until cool. Refrigerate for up to 2 weeks.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/slow-cooker-pork-roast-pickled-grapes/