What is umami? According to Japanese scientists, it's the fifth flavor, rounding out the well-known quartet of sweet, salty, bitter, and sour. Yet it's a taste that's been hard for Americans to identify—or at least it was, before Adam Fleischman opened Umami Burger to great fanfare. ("His face belongs on the Mount Rushmore of the burger world," GQ said, naming his creation 2010's Burger of the Year.) Below, we chatted with Luke Forzano, director of culinary operations at SLS Las Vegas, about the top five reasons to visit the gourmet burger joint.

1. Umami Burger basics are anything but: The patties, served juicy and medium rare unless otherwise requested, are made with beef ground fresh every morning. And the "beautiful, Portuguese buns," as Luke calls them, are made with a secret house recipe, as is the tangy ketchup.

2. The menu will expand your vocabulary: Not only will you better understand umami, which Luke calls a "depth of flavor [gotten] through cooking and caramelization"—you might learn new words from the creative toppings. For instance, parmesan frico is aged parmesan, caramelized and baked into a flat cracker.

3. They'll drizzle fondue on a burger: Two house burgers come with California cheese: a white cheese fondue made with a hint of sherry.

4. They honor local culture wherever they go: The Vegas location has an on-site sportsbook.

5. They have the celebrity seal of approval: They recently put out the Mindy Burger, a limited-release collaboration with Mindy Kaling. "Spicy and cheesy, it reflects my own personality," she told People.