Season the chops: Pat the pork chops dry. Season both sides with salt and pepper.
Let them sit at room temperature while you prep the onions.
Heat the Dutch oven: Place a heavy Dutch oven over medium-high heat. Add the oil and warm until shimmering.
Sear the pork chops: Lay the chops in the pot without crowding. Sear 2–3 minutes per side until well browned.
Transfer to a plate and set aside. Do this in batches if needed.
Cook the onions: Reduce heat to medium. Add the sliced onions and a pinch of salt.
Cook, stirring occasionally, for 8–10 minutes until soft and golden around the edges. If the pot looks dry, add a splash of oil.
Add garlic and tomato paste: Stir in the garlic and tomato paste. Cook 1 minute until fragrant and slightly darkened.
Deglaze: Pour in the wine (if using).
Scrape up the browned bits from the bottom with a wooden spoon. Simmer for 1–2 minutes to reduce slightly.
Build the sauce: Add the broth, Worcestershire, Dijon, thyme, bay leaf, and any juices from the plate with the chops. Stir to combine and bring to a gentle simmer.
Nestle the chops back in: Return the pork to the pot, submerging them partly in the onions and sauce.
The liquid should come about halfway up the chops.
Cover and cook: Cover the Dutch oven and reduce heat to low. Simmer for 20–25 minutes, turning the chops once halfway through. You want the pork just cooked through and tender.
Internal temp should reach 145°F.
Finish the sauce: Remove the chops to a plate and tent with foil. Discard the bay leaf. If you want a slightly thicker sauce, simmer uncovered for 3–5 minutes.
Stir in the butter for a glossy finish. Taste and adjust salt and pepper.
Serve: Spoon onions and sauce over the pork chops. Garnish with parsley if you like.
Serve with mashed potatoes, egg noodles, rice, or crusty bread.