When two men are engaging in anal sex, and the man who's inserting his penis' balls slap against the other man's anus, to an extent where a fudge-like coating of feces over both nuts is created.

Also, a kind of coffee.
"We were going at it so hard I had a double nut fudge"

or

"Are you going to have the double nut fudge, or try the Brooklyn brew?"
by xylobone November 9, 2009
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