Pat the brisket dry with paper towels. Combine kosher salt, black pepper, smoked paprika, and garlic powder in a small bowl. Rub the spice mixture evenly over all sides of the brisket; let rest at room temperature for 30 minutes (or refrigerate up to overnight for deeper flavor).

Sear

Preheat oven to 150°C (300°F). Heat vegetable oil in a heavy Dutch oven or ovenproof pot over medium-high heat until shimmering. Sear the brisket 4–5 minutes per side, until a deep brown crust forms. Remove brisket and set aside.

Braise

Add the quartered onion to the pot and cook 2–3 minutes until softened. Return the brisket to the pot, pour in beef broth and apple cider vinegar so liquid comes about halfway up the brisket. Add bay leaves. Cover tightly with lid and transfer to the preheated oven.

Low and Slow Cook

Braise for 3 to 3½ hours, or until the brisket is fork-tender and an instant-read thermometer inserted into the thickest part reads about 90–95°C (195–205°F). Check once halfway and spoon some braising liquid over the top if it looks dry.

Rest

Remove the pot from oven. Transfer brisket to a cutting board and let rest, covered loosely with foil, for 20 minutes. Reserve the braising liquid for the sauce.

Sauce & Finish

Make Sauce

Strain 200 ml of the reserved braising liquid into a saucepan, discarding solids. Add barbecue sauce, Worcestershire sauce, brown sugar, and hot sauce. Bring to a simmer over medium heat and cook 5–8 minutes until slightly reduced and glossy. Taste and adjust seasoning.

Chop Brisket

Using two forks or a coarse chop, shred/chop the rested brisket into bite-sized pieces. Combine chopped brisket with about half of the warm sauce in a bowl to moisten (reserve remaining sauce for serving). If you prefer saucier sliders, mix more sauce to taste.

Sliders

Toast Buns

Preheat a skillet or griddle over medium heat. Lightly butter the cut sides of the mini buns. Toast, cut-side down, 1–2 minutes until golden and slightly crisp.

Assemble

Spread a thin layer of yellow mustard on the bottom half of each bun. Place a generous spoonful of chopped brisket on top. Add a small heap of cole slaw (or shredded cabbage), a slice of dill pickle, and some pickled red onion if using. Cap with the top bun. Repeat to make 12 sliders.

Finish (optional)

Warm any reserved sauce and drizzle a little over the assembled sliders or serve on the side. Sprinkle chopped chives and sesame seeds on top if desired.

Serving

Serve the sliders hot, with extra barbecue sauce and pickles on the side. Leftover chopped brisket keeps in an airtight container in the refrigerator for up to 4 days.