FuthaMukka is the correct spelling for the toned down version of MotherFucker. As a spoonerism FuthaMukka can be used with out offence in polite company or to avoid censorship.

It is rarely used as an insult as FuthaMukka is considered a complement when prefixed with words like bad, sexy, dirty etc.
Bad FuthaMukka, Sexy FuthaMukka, Dirty FuthaMukka
by Bad Ass futhamukka October 14, 2009
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Play on words of the phrase m*ther f*cker

Also a range of clothing available to buy online.
by Tinks21 December 11, 2009
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