I watch sooooo many clips for this part and I still wondering
BB spoke Canto or Mandarin?? when he said 王嘉尔 ~~ I knew some mandarin so at first I thought he was sayin 'wo xi huan Beijing kao ya' but after reading comment a lot of ppl say that he speak canto 'I wanna hit him(?)' which is clearly explained JS's reaction but whenever I listened to it still 'I like Beijing Roasted duck' lol