I've not tried Gong Bao Ji Ding before, which is a shame, the only thing I can think of which has gong in the name and is a food is gong wan (specifically gong wan tang), which is a type of wan zi (meat ball), in a soup
Speaking of favorite Chinese foods (specifically real ones in Taiwan), my favorites are as follows:
fried dumplings. (breakfast)
Dan Bing (a type of omelet with a kind of tortia style bread in it with sping onions and soy sauce, lovely) (breakfast)
Lu Rou Fan (meat cooked in soy sauce and rice wine among other herbs for a long time with rice and usually served with a Lu Dan, (an egg) cooked in the same style) (DINNER)
Dou Jiang with Yo Tiao (soy bean milk with "oily stick") (breakfast)
Dao Shao Niu Rou Mien (spicy beef noodle soup with specially knife cut noodles, served with pak choi (I like it with pak choi anyway)) (DINNER)
Ma Jiang Mien (sesame sauce noodles, you can easily make this at home, get some Tahini (sesame sauce, looks a bit like peanut butter), mix with soy sauce, about two tablespoons with two tablespoons of tahini and chuck a load of noodles on top, mix and savour! It's SO lovely!!) (DINNER!)
I like loads of veggie dishes in Taiwan, I particularly like Kong Shin Cai (hollow vegetable), a type of greens, cooked with garlic and maybe some chili, it's got to be piping hot and ate as such too. I also like Bai Cai (Chinese leaves), Pak Choi (I can never seem to remember the correct mandarin pronunciation for this) and the very difficult to find "Long Xu Cai" (dragon's whiskers vegetable).
Lovely stuff!