Preheat oven to 325° F.

Heat olive oil in a large heavy bottomed ovenproof pan over medium high heat. Add flanken and cook until nicely browned, about 3 to 4 minutes per side. Add ¾ cup bbq sauce and 1 cup water and bring to a boil. Reduce to a simmer, cover and transfer to oven. Cook 2 hours or until meat is tender and falling off the bone.

About 30 minutes before meat is done, marinate cabbage. In a small bowl, toss cabbage with vinegar. Let sit 15 minutes. Stir again and let sit 15 minutes more. Drain before serving.

Remove meat from pan and discard bones. Shred into small pieces. To assemble sliders, spread 1 tablespoon of remaining bbq sauce on each bun. Top with ¼ cup shredded meat and 2 tablespoons pickled cabbage.