Season the oxtails with 2 tsp kosher salt, and 1 tsp black pepper. Drizzle the worcestershire sauce all over the oxtails, then toss the oxtails to make sure that they are coated. Next, sprinkle 1/4 cup of flour all over the oxtails, and make sure that the oxtails are coated with the flour. Next pour the vegetable oil into a large pan, and place the pan over medium heat. Once the oil is nice and hot, add the oxtails in, and brown them. Once the oxtails are nice and brown remove them from the pan, and put them in the slow cooker. Return back to the pan with the hot oil. If they are burnt pieces in the pan, pour out the oil, strain, clean the pan, then pour the strained oil back into the pan. Start adding the remaining flour into the pan, but only a little bit at a time. Whisk continuously.
