Sear the beef briefly in a pan. Transfer the beef into the crock pot. Deglaze the pan with the dashi stock, then add the broth to the crock pot. (These steps are optional, but give the soup a deeper flavor.)

Add the kimchi, hot pepper paste, black bean sauce, onion, and tofu to the crock pot. Set the crock pot to cook and let the hot pot simmer for at least two hours.