Season the pork chops. Pat the pork chops dry with paper towels. Season both sides with salt, pepper, garlic powder, and onion powder.
Coat lightly with flour. Place the flour on a plate and dredge each pork chop, shaking off any extra. This helps the chops brown well and gives the gravy a little body later.
Brown the pork chops. Heat the olive oil in a large skillet over medium-high heat.
Add the pork chops and cook for 3 to 4 minutes per side, until golden brown. Remove them from the skillet and set aside.
Cook the onions. Lower the heat to medium and add the butter to the same skillet. Add the sliced onions and cook for 8 to 10 minutes, stirring often, until soft and lightly golden.
Add the garlic and build flavor. Stir in the minced garlic and cook for 30 seconds.
Pour in the chicken broth, then add the Worcestershire sauce and thyme. Scrape the bottom of the skillet to release any browned bits.
Thicken the gravy. Mix the cornstarch and cold water in a small bowl until smooth. Stir it into the skillet and let the gravy simmer for 2 to 3 minutes, until it starts to thicken.
Return the pork chops. Place the pork chops back into the skillet and spoon some gravy over the top.
Cover the pan, reduce the heat to low, and simmer for 10 to 15 minutes, or until the pork is cooked through and tender.
Finish and serve. Taste the gravy and add more salt or pepper if needed. Garnish with parsley if you like, then serve the pork chops hot with plenty of onion gravy spooned over the top.