Fry bacon in large skillet over medium heat until lightly browned, about 8 minutes. Using slotted spoon, transfer bacon to paper towels, leaving fat in pan (you should have 2 T fat; if not, supplement with oil). Refrigerate bacon.
Heat fat over high heat until smoking. Meanwhile, pat pork chops dry with paper towels and sprinkle with salt and pepper. Cook 3 chops until golden brown on both sides, about 3 minutes per side. Transfer chops to slow cooker insert. Repeat with remaining chops and transfer to slow cooker insert.
Pour off all but 1 t fat from skillet, add onions, 1 t brown sugar, 1/4 t salt, and 1/4 cup water to now empty skillet. Using wooden spoon, scrape browned bits from pan bottom and cook over medium high heat until onions are soft, about 6 minutes. Stir in garlic and thyme and cook until fragrant, about 30 seconds longer. Pour onion mixture over chops in slow cooker insert. Add broth, soy sauce, and remaining 1 T brown sugar to skillet, bring to boil, and add bay leaves. Pour mixture over onions in slow cooker.
Cover slow cooker and cook on low until pork is very tender, about 8 hours (or cook on high for 4 hours).
When ready to serve, reheat bacon in large saucepan until crisp and transfer to small bowl. Carefully transfer chops to serving platter with large spoon and tent with foil. Discard bay leaves and pour liquid through mesh strainer into now-empty saucepan. Transfer solids to blender with 1 c liquid and blend until smooth. Stir back into remaining liquid in saucepan. Mix cornstarch and remaining 2 T water together in small bowl and stir into sauce. Cook over medium heat until thickened, about 8 minutes. Add vinegar, season with salt and pepper, pour over chops, and sprinkel with bacon and parsley. Serve.