Heavily season the chuck roast with salt and pepper on both sides.
Bring a large, heavy-bottomed pot to medium-high heat and add the beef, searing on both sides until nicely browned.
Remove the beef to a plate, add the onions and garlic, and cook until the onions just begin to brown at the edges.
Return the beef to the pot, pour over the broth, and add the pepper. Bring to a simmer, then reduce the heat to low, cover, and allow to cook for around two hours, or until it is tender and easily shredded. Remove from heat
Remove the meat from the pot and shred with two forks. Return the shredded meat to the pot, stir in the vinegar, and add salt to taste.
Serve on toasted buns with plenty of caesar slaw (see link in text)
