A slider is a thin, thin slip of beef, cooked on a griddle with onions and pickles piled atop patty. The steam from the onions does as much cooking as the griddle. The buns are placed atop the onions, absorbing the pungent aroma and flavor.

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"Here's a neat video showing the Shake Shack cooking process. It illuminates a process that is somewhat behind-the-scenes and reveals that the Shake Shack uses the "smash" technique. I've talked about the smashed-burger technique here, but if you missed that, it may surprise you to know that I'm in favor of this method. While it runs counter to everything you hear—that you should handle the meat as little as possible and never, ever press down on it—the smash technique (especially when employed on a hot, hot griddle) creates all sorts of great crunchy-chewy bits on the patty surface."

When it comes to seasoning, burger cooks fall into two camps: those that season only the exterior of the patty just before cooking, and those that work the salt and pepper right into the meat. I've always been a member of the first camp—it's just the way I was taught to make burgers, and I've blindly followed the method since then. Then I got to thinking: French training emphasizes the importance of seasoning every component of a dish so that every bite is well-seasoned. So shouldn't a burger be better if you season the meat before forming the patties? Or better yet, even before it's ground so that the salt is evenly distributed throughout the entire burger instead of concentrated on the exterior? Could all those other burger cooks actually be right?