Aunt Jemima 'Heirs' -- Cutoff From Pancake Billions ... You Need Batter Proof

Two guys claiming to be heirs to the real life Aunt Jemima couldn't pour it on thick enough to convince a judge -- their shot at $3 billion just got tossed out of court.

According to docs obtained by TMZ ... D.W. Hunter and Larnell Evans, Jr. went to court armed with a pretty thin story to prove they're the great-grandsons of Anna Short Harrington -- who portrayed Aunt J. from 1935 until the '50s.

As TMZ first reported ... the men sued PepsiCo, Quaker Oats, and 2 other companies for royalties they feel Harrington had been screwed out of while her image was being used to hawk flapjacks.

Once they got to court ... Hunter told the judge his grandmother once gave him a photo of Harrington -- a photo he no longer has -- and claimed that proved his relation. Hunter and Evans also said they tried to locate Harrington's grave in Syracuse, NY.

Not shockingly, the judge said that so-called evidence fell flatter than a ... well, you know.