"Mix the soda and soup together [in the slow cooker]. Put the roast in [2-3lbs, well-marbled is best] then sprinkle the seasoning packet on top of the roast. I flip it halfway. The longer you can roast the better. I do 12 hours on high."
And you won't be able to get away with a low-sugar option, she warns - once she tried using Diet Coke and "it was disgusting".
Some Facebook users praised her genius, while others slammed the idea of simply pouring Coke and soup over a cut of beef.
"Look at that lovely piece of beef, I know I'll pour loads of diluted sugar all over it. Not for me thanks," wrote one.
"Why the sugar-loaded drink? More dental bills," wrote another.
One wrote, "Looks intriguing, I'd love to see it once it's cooked."
But the Coke option might not be so unusual after all, as some pointed out that beer. which contains sugar, is also often used as a marinade.