Combine the thyme, paprika, pepper, salt, onion powder, garlic powder and cumin in a small bowl. Rub spice mixture all over the top of the brisket.
Pour 1 cup water in the bottom of a large 7 quart slow cooker. Place the spice covered brisket, fat side up, in the water. Pour the liquid smoke and Worcestershire sauce over top of brisket. Cover with lid and cook on Low heat for 8 to 10 hours. (I like to cook mine the full 10 hours.)
Once done cooking, carefully remove brisket to a large platter. Remove fat from bottom of brisket. It should easily skim right off. Discard fat. Shred brisket.
Place shredded brisket back in slow cooker and pour the barbecue sauce all over the top. Gently stir. Cover with lid and cook another 30 minutes or until sauce is heated through. Serve brisket warm and enjoy!