1)
Yang: 你要什么?
Mei: 你有不有拉面?
Some racist or immature kid:
Ching chong ching chong
Mei: Say that again and I'm going to pound your face in.
2)
Japanese language professor: こんにちは!大丈夫ですか?
Ignorant racist kid: Ching chong
Japanese language professor: Actually Japanese can't pronounce "ching chong" properly, and isn't in the same language family as any of the Chinese languages. So that's as intellectually incorrect as making fun of English by saying "
derka derka derka" .