Heat olive oil in a skillet over medium-high heat and sear the brisket 3–4 minutes per side until browned.
Place sliced onion in the bottom of the slow cooker.
Lay the brisket on top of the onions.
In a bowl, mix BBQ sauce, beef broth, brown sugar, Worcestershire sauce, paprika, garlic powder, salt, and black pepper.
Pour the sauce evenly over the brisket.
Cover and cook on LOW for 8–10 hours or HIGH for 5–6 hours until the meat is fork-tender.
Remove brisket and slice or shred as desired.
Return the meat to the slow cooker and toss in the sauce.
Let sit 10 minutes before serving to soak up more flavor.
Serve on buns, over rice, or with sides like coleslaw or potatoes.
