Preheat your smoker to 225°F using oak or hickory wood for an authentic Texas flavor profile.
Trim any excess hard fat from the brisket flat, leaving about a quarter-inch of the fat cap intact.
In a small bowl, combine the sea salt, black pepper, garlic powder, onion powder, and smoked paprika.
Rub the spice mixture evenly over all sides of the brisket, pressing it firmly into the meat.
Place the brisket in the smoker and cook until the internal temperature reaches 165°F, usually taking several hours.
Wrap the brisket tightly in un-waxed butcher paper and return it to the smoker until the internal temperature reaches 203°F.
While the meat finishes, whisk together the tomato paste, apple cider vinegar, maple syrup, Dijon mustard, and water in a small saucepan over low heat to create the glaze.
Toss the broccoli florets with avocado oil and roast in a 400°F oven for 15 minutes until the edges are crispy.
Remove the brisket from the smoker and let it rest in the paper for at least 30 minutes before slicing against the grain.
Serve the sliced brisket drizzled with the warm BBQ glaze alongside the roasted broccoli.