01 - Preheat oven to 300°F.
02 - Pat the brisket dry with paper towels. Season evenly on all sides with smoked paprika, chili powder, cumin, salt, and black pepper.
03 - Heat olive oil in a large Dutch oven over medium-high heat. Sear brisket on all sides until deeply browned, about 8 minutes total.
04 - Remove brisket and set aside. Add sliced onion and minced garlic to the pot, sautéing for 2 to 3 minutes until softened and fragrant.
05 - Return brisket to the pot. Pour in beef broth and barbecue sauce. Cover tightly with the lid.
06 - Transfer the covered pot to the oven. Cook for 4 hours, or until the brisket is fork-tender and easily shreds.
07 - While brisket cooks, combine green and red cabbage, grated carrot, mayonnaise, apple cider vinegar, Dijon mustard, sugar, salt, and pepper in a large bowl. Mix thoroughly. Refrigerate until ready to use.
08 - Transfer cooked brisket to a cutting board. Using two forks, shred the meat into bite-sized pieces. Toss with some of the cooking juices and additional barbecue sauce if desired.
09 - Layer a generous portion of shredded brisket on the bottom half of each slider bun. Top with coleslaw and pickle slices. Close with the top bun half.
10 - Serve sliders immediately with extra barbecue sauce on the side for drizzling.