Preheat the oven to 400°F. Heat the butter or oil in a large sauté pan on medium high heat. Pat dry the chops with paper towels. Lightly salt the pork chops then brown each side in the sauté pan. Cook just enough to brown, then remove from pan and place into a high-sided baking dish or roasting pan. (If your pork chops are very thin and have cooked through at this point, skip the oven step and tent them loosely with aluminum foil while making the sauce.)

Add the minced onion to the sauté pan in which you browned the pork, and sauté for 2-3 minutes, until the onion begins to brown. Add the vinegar, chili powder, pepper, maple syrup, water, and Worcestershire sauce to the pan and bring to a boil. Pour this sauce over the pork chops in the baking dish. Lower the heat to 350°F and bake uncovered for 10-15 minutes for thick (1-inch thick) chops, 5-10 minutes for thin (1/2-inch thick) chops, or until the interior of the pork reaches 145°F.

Optional In the same sauté pan that you used to make the sauce, add a little oil and heat to medium high. Cook the sliced onions in the pan, allowing the onions to pick up any sauce remaining in the pan. Cook until lightly browned, while the pork chops are baking.

Place the pork chops on a serving platter and loosely tent with foil. Pour the sauce into the saucepan you seared the chops in and whisk in 1 tablespoon flour to thicken the gravy. Salt to taste, and serve the gravy over the chops and (optional) onions.