Come to think of it maybe 4 to 5+ years ago I had a beef chao at Trieu Chau in Santa Ana.
Granted Trieu Chau is Vietnamese Chinese (with Chiu Chow Chinese roots) and pretty much every goes for their noodle soup or dry noodles/broth on the side mostly. But they do have chao there and it was very tasty in memory. This is not Vietnamese Chao, but at the restaurant it is listed and categorized as Chao (with the Chinese character for jook listed as well).
From memory it was really good, as if they added some of the bone/meat stock or used it to cook at some point. Good thickness and almost done in a style of Hong Kong Cantonese Chiu Chow congee but different (for a fairly legit Chiu Chow congee HK Cantonese style, the version at Seafood Palace is pretty legit). So in a way, a hybrid between Hong Kong Cantonese jook, Chiu Chow jook, and Vietnamese Chao, more slanted towards Cantonese style a bit.