01 -
Combine chili powder, garlic powder, celery seeds, and black pepper in a small bowl and mix well.
02 -
Rub the seasoning mixture thoroughly over all surfaces of the brisket. For enhanced flavor, optionally cover and refrigerate overnight.
03 -
Place the brisket in the base of a 6-quart slow cooker. In a separate bowl, stir together all sauce ingredients until well combined.
04 -
Pour the sauce evenly over the brisket, cover the slow cooker, and cook on low heat for 6 to 8 hours until tender.
05 -
Remove the brisket from the slow cooker and slice thinly across the grain to ensure tenderness. Optionally, drizzle with reserved cooking liquids before serving.