In a small bowl, combine paprika, garlic powder, onion powder, brown sugar, salt, and black pepper. Rub the spice mixture all over the brisket, covering it completely.
Place the seasoned brisket in the slow cooker.
In another bowl, whisk together beef broth, Worcestershire sauce, apple cider vinegar, and tomato paste. Pour the mixture over the brisket in the slow cooker.
Cover and cook on low for 8-10 hours or on high for 4-5 hours, until the brisket is tender and easily shreds with a fork.
Once cooked, remove the brisket from the slow cooker and let it rest for 10-15 minutes before slicing agains