Just in case you might want something a little different ....
My aunt called these 'Western burgers'.
Brown ground beef like you were making sloppy joes, drain the oil.
Now the different part
Add cubes of Velveta cheese. Just keep adding until all the beef is coated to your taste (similar to the amount of 'sloppy' you like in your sloppy joe). Now add sliced black olives.
That's it.
We used to make a big pot full, fill the buns and wrap them in foil and freeze them. Then just pop the whole thing in the oven to warm - bun gets nice and toasty.
Hmmm ... want to make a big pot now.