For the Brisket:
Rub all sides of the brisket with Tarheel BBQ Rub. In a large cast iron skillet, sauté the onion in 1 tablespoon olive oil over medium heat, until translucent and browned. Remove and set aside.
Increase the heat to medium-high and add an additional tablespoon of olive oil. Sear the brisket on both sides. Transfer the brisket, fat side up, to a slow cooker and top with the sautéed onions.
In a small bowl, combine the broth, Worcestershire sauce and soy sauce. Pour the mixture around the brisket.
Cook on high for 6 hours or low for 8 hours, until the meat is fork tender.
At this point, you need to remove the fat from the brisket and juices. If you are making this a day ahead, allow the cooker to cool and store it in the refrigerator overnight. The fat will solidify and you can easily remove it. If you're serving right away, remove the brisket and transfer the juices to a gravy separator. Pull any large pieces of fat from the brisket and pour off the juices from the fat.
Chop or pull apart the brisket and combine with the juices in a large skillet. Warm over low heat and adjust seasonings to taste.
For the Sliders:
Preheat the oven to 300 degrees F and lightly oil a 9x13" baking dish.
In a medium skillet, sauté the onion in oil with salt and pepper until soft and lightly browned.
Slice the rolls in half and arrange the bottom halves snugly in the baking dish. You may have a few left over. I call them snacks.
Mound the bottom of each bun with a generous dollop of meat, 1 tablespoon of onions and a pickle. Spread mustard on the bun tops and put one on each slider.
Cover the pan with foil and bake 10 minutes. Serve warm.