Place the chuck roast on a large cutting board and slice into large chunks. To aid the sear, Pat-dry the meat on both sides.
Season both sides generously with coarse salt and black pepper, set aside.
Grease a large skillet with olive oil and bring to a high heat to sear the seasoned chuck roast on both sides.
Sear the chuck roast for three minutes on each side or until a golden brown crust is achieved. Set aside in your slow cooker/crockpot with the residual rendered fat (beef drippings) from the pan.
Wash your scallions, fresh basil leaves, and pear, set aside. Chop the peeled pear and white onion into chunks for pureeing. Additionally, separate the four garlic cloves.
Taste a small sample of the pear to monitor the sweetness level, this will determine if the brown sugar is needed (in case your pear is not ripe).
Add the rice wine vinegar, sesame oil, sriracha, Korean BBQ sauce, ginger paste, garlic cloves, pear, onion, basil, and brown sugar into a food processor or blender; puree until smooth (a few chunks is acceptable).
Pour the puree over the sear chuck roast into the crockpot. Sprinkle garlic and onion powder, followed by the beef broth to cover the chuck roast.
Cover the crock pot with a lid and set on high for 4 hours.
Once the Korean-style pot roast is fork tender serve with jasmine rice and vegetables.