In a medium bowl, mix together salt, black pepper, smoked paprika, garlic powder, onion powder, and optional chili powder. Rub the mixture all over the brisket and let sit for 20 minutes.

Heat olive oil in a large skillet over medium-high heat. Sear the brisket for 2-3 minutes on each side until golden-brown.

In the slow cooker, combine the seared brisket with beef broth, barbecue sauce, Worcestershire sauce, Dijon mustard, brown sugar, onion, and minced garlic. Cook on low for 8 hours.

Remove brisket and let it rest for 10-15 minutes before shredding into bite-sized pieces.

In a skillet over medium heat, melt butter and combine with reserved cooking liquid, brown sugar, beef drippings, and Worcestershire sauce. Stir and add shredded brisket to caramelize for 5-7 minutes.