I think "coffee black" or other similar combinations can be correctly used only in certain structures like "I like (to have) my coffee black", and cannot be used in others (e.g. you can't say "This is coffee black".)
As for the "mission impossible", it can be used as a movie or a newspaper article title or in technical language. In such cases the linking verb "be" can be omitted, so you get "Mission Impossible". But do not trust me, it's only IMHO.
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