In the "lost interview" of Bruce Lee with Pierre Berton (1971) he says "Tai Chi Chuan" is Mandarin, but I don't fully get the Cantonese version when he tells it.
I hear "Tai te kuen" ... but I'm not sure at all.
It's pronounced: Tai 'cake' kuen
Taichi chuen is mandarin
The site mdbg has audio of native Mandarin and Cantonese speakers. See the entry for taijiquan. You need to click on the characters for taijiquan as below in the screenshot to access the audio, which is circled for Cantonese in red.
Unfortunately, the middle word is missing Cantonese audio.