Right! Got a friend with a Blackstone. Now what?
get some 80/20 ground beef
roll it into balls about 1.5 inches in diameter
heat up the blackstone
place a sheet of parchment paper on top of the ball of meat on the grill and smash it super flat with a plate, or cast iron pan or whatever is large and flat, about 1/4-1/2" thick for best results after smashing remove the parchment paper
let the burger crisp up and SCRAPE it off the blackstone with a big old scraper or wallpaper scraper, flip it and cook again till crispy, right after the flip put DELI American cheese on the burger and let it melt
I like to make doubles, but I think you can take it from here as all you have to do it put it on a bun