Preheat your oven to 300°F (150°C).
In a small bowl, mix together the salt, black pepper, smoked paprika, garlic powder, onion powder, and cayenne pepper (if using).
Rub the spice mixture all over the brisket, ensuring it is evenly coated.
In a large oven-safe skillet or roasting pan, heat the olive oil over medium-high heat. Once hot, sear the brisket on all sides until browned, about 3-4 minutes per side.
Remove the brisket from the skillet and set aside. Pour the beef broth into the skillet, scraping up any browned bits from the bottom.
Return the brisket to the skillet, fat side up. Cover the skillet tightly with aluminum foil or a lid.
Place the skillet in the preheated oven and roast for 4 to 5 hours, or until the brisket is fork-tender.
Remove the brisket from the oven and let it rest for 20-30 minutes before slicing.
Serve with barbecue sauce drizzled on top or on the side.