Where does "Black people don't eat mayo/Mayonnaise is a white people food" come from?

Please get your eyes checked. Whipped cream is white. Mayo is a pale yellow. Put some of each next to each other, you will see a clear difference.

Unless you speak of that abomination called Miracle Whip, which is NOT mayo. That crap might be white, I haven’t seen an open jar in decades.

Miracle Whip is the reason that, for years, I thought I did not like mayo. I mistakenly thought it was mayo. When I finally tried the real thing, it was a revelation.

In Hannah and Her Sisters (I think) Woody decides to convert to Christianity and goes shopping. He unpacks a paper bag with a crucifix, a Bible, a loaf of Wonder Bread and a jar of mayo.
I saw this in a theater in Houston. Only one person besides me laughed.