That's Joey Chestnut in the middle of pounding 32 Big Macs on Thursday ... and, yeah, it's the most disgusting/awesome thing you'll see all day.

The competitive eating legend posted the video on his social media ... saying he was having a cheat day and wanted to accomplish something he -- nor any other person -- had ever done.

So, the dude set out to grab a McDonald's world record ... and fired up his phone to get 15.36 POUNDS of Big Macs delivered to his crib.

What happened next is pretty graphic ... he slammed all 32 burgers -- pickles, lettuce, special sauce and all -- and sweated ruthlessly throughout the meal!!

But, in true Chestnut fashion ... he dominated the challenge -- setting the world record (it had previously been 30) -- and afterward, he looked pretty damn good for a guy that consumed 18,016 calories in less than an hour!!

Of course, Joey's used to these kinds of feats ... he owns the annual Nathan's Hot Dog-Eating Contest, eating a record 74 wieners back in 2018.