Mix together the brown sugar, paprika, salt, black pepper, chili powder, garlic powder, onion powder, and cayenne pepper to make the dry rub.
Pat the brisket dry with paper towels. Rub the dry rub all over the brisket, covering all sides. Wrap the brisket well in foil wrap.
Place the brisket on a baking sheet fat side up. Cook for 3 hours.(can be made in advance and rewarmed in a 350℉ (176℃) oven).
Then set aside to rest for about 30 minutes before slicing.
While the brisket is resting, warm the barbecue sauce in a saucepan over low heat.
Slice the brisket against the grain into thin slices.
Brazilian Tomato Slaw:
Mix all ingredients for slaw. Let stand at room temperature until flavors combine, about 3 hours.
Chipotle Sweet Potatoes:
Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.
Toss sweet potatoes and melted butter together in a large bowl.
Whisk brown sugar, onion powder, garlic powder, chipotle chile powder, salt, and black pepper together in a small bowl; sprinkle over sweet potatoes and toss to coat. Pour potatoes in a single layer onto the prepared baking sheet.
Roast in the preheated oven until potatoes are tender, 30 to 45 minutes.
To Serve:
Assemble the Texas brisket sandwich by placing slices of brisket on the hamburger buns, topping with barbecue sauce, and optional pickle slices. Serve with chipotle sweet potatoes, Brazilian tomato slaw, and a cold amber ale.