What makes up a really great burger? Is it a homemade bun and lots of fixings or simply high quality meat? That's what the folks at Nation's Restaurant News set out to discover, and, they chose some of the most well known amongst burger purists. Check out their picks for home grilling inspiration from the likes of Shake Shack and Bobby Flay. It will be no surprise that each of these burger shrines has a different formula to an awesome burger. Five Napkin Burger swears by Gruyère cheese. Shake Shack uses potato roll buns and their signature sauce. And McDonalds -- well, we suppose they qualify as an iconic burger joint as well -- is all about the sesame bun and two slices of American cheese. Don't miss Bobby Flay's burger piled high with potato chips!