Preheat your grill or smoker to 225°F.
Combine the brown sugar, paprika, garlic powder, onion powder, salt, black pepper, and cayenne pepper to create a dry rub.
Rub the dry mixture evenly on all sides of the beef brisket.
Place the brisket on the grill or smoker.
Cook the brisket for approximately 6-8 hours or until it reaches an internal temperature of 195°F - 205°F.
While brisket is cooking, prepare the slaw and toppings.
Remove brisket from heat and let it rest for about 30 minutes.
Shred or chop the brisket into bite-sized pieces.
Warm the tortillas on a skillet or directly on the grill for about 30 seconds to 1 minute per side.
Assemble the tacos by adding the shredded brisket, fresh veggies, and shredded cheese to the tortillas.