Preheat the oven to 300°F.
Pat the chuck roast dry, then season very well on all sides with salt and black pepper.
In a bowl, whisk together the brown sugar, Bachan's Japanese Barbecue Sauce, garlic, ginger, sesame oil, rice vinegar, onion powder, and garlic powder.
Heat a Dutch oven over medium-high heat with a little oil and sear the chuck roast on all sides until deeply browned.
Pour the sauce over the meat, cover with a lid, and transfer to the oven.
Cook for 3 to 3½ hours, until the meat is very tender and easily shreds.
Serve with rice or mashed potatoes and roasted vegetables.
