For the barbecue sauce:
1 1/2 C ketchup
1/2 C packed dark brown sugar
1/2 C water
1/4 C finely chopped yellow onion
3 T cider vinegar
3 T Worcestershire sauce
2 chipotles in adobo sauce, finely chopped
1 tsp garlic powder
3/4 tsp freshly ground black pepper

For the brisket:
1/4 C paprika
1 T chili powder
1 T ground cumin
1 T packed dark brown sugar
1 T kosher salt, plus more as needed
1 tsp cayenne pepper
1 tsp garlic powder
1 tsp freshly ground black pepper, plus more as needed
1 (5 lb) beef brisket)