Season the pork chops with whatever seasonings you'd prefer (I used salt, pepper, garlic powder and a little steak seasoning blend). Place them in a greased slow cooker and sprinkle the onions over the top. In a bowl, whisk together the root beer, BBQ sauce, Worcestershire and garlic. Pour the sauce over the chops and place the lid on. Set the heat to low and let them cook for 4 hours (longer if your using thicker cut pork chops)

When the 4 hours is up, pour the sauce from the slow cooker into a saucepan and whisk together 1 tbsp of cornstarch into 2 tbsp of water. Whisk the cornstarch slurry into the sauce and set it over med-high heat until it comes to a simmer. It'll thicken pretty quickly. Then serve the pork chops with the sauce poured over them.