Combine cold water, salt, peppercorns, and bay leaf for brine in a bowl. Place pork chops in a shallow baking dish and pour the brine over top. Let sit for 1 to 2 hours.

Meanwhile, combine brown sugar, garlic powder, paprika, onion powder, mustard powder, salt, and pepper for rub in a small mixing bowl.

Preheat the oven to 400 degrees F (200 degrees C).

Remove pork chops from brine, rinse under cold water, and pat dry. Rub pork chops generously on both sides with the seasoning mix. Discard brine.

Heat a cast iron skillet over medium-high heat. Add oil to the hot skillet. Add pork chops to the hot oil and sear until browned, 2 to 3 minutes.

Turn pork chops and place skillet in the preheated oven. Bake until no longer pink in the center, 6 to 8 minutes. Remove from the oven, tent with aluminum foil, and let rest for 5 minutes before serving.