[hadoːkẽꜜɴ]

Or if the IPA is not helpful:

“Ha” as in “hard” but with a shorter vowel, not the æ thing from “had”.

“Door” without the R - the stress is here (hadouken). The important part is avoiding “oh” which sounds extremely thickly Anglo (“chipoohhhtlayyyyyy”)

Ken is ken, I guess.