Preheat oven to 350 degrees. In a large cast iron skillet, preferably with tall sides, heat a small amount of vegetable oil over medium high heat. Add the pork chops that you have seasoned with salt and pepper. Brown on both sides for 7 minutes per side. Add water to about 3/4 the way up the sides of the pork. Cover tightly with lid and place in a 350 degree oven for about an hour. (This is called braizing) Remove meat, set aside and keep warm. Heat the skillet with the remaining water and drippings to a boil. Mix the flour and a little water in a container to make a slurry. Add to the boiling drippings and stir. When it comes back to a boil, add more water if necessary to thin gravy. Add salt and pepper to taste. Simmer 5 minutes. Serve with mashed potatoes.