Can’t remember where I found this online, but it is purported to be Ernest Hemingway’s own hamburger recipe.
A quick search turned up this article, which actually recreated the burger (with substitutions for unavailable ingredients): https://www.artofmanliness.com/living/food-drink/ernest-hemingways-favorite-hamburger/
This actually looks pretty darn awesome. I have never heard of mei yen powder, and it looks like it’s discontinued.
Here is a substitute recipe someone got from Spice Islands.
https://everything2.com/user/Venkman/writeups/Mei+Yen+seasoning
Presumably there is some salt in those spice islands seasoning blends? Kinda been moving away from really thick burgers and more to the smash burger end of the spectrum lately. Also, cloves? Maybe that seemed less odd so long ago?
That’s cloves of garlic.