Fantastic burgers, delicious beer, and excellent service! The hubby and I ate here one night while staying at the Luxor (which is connected to Mandalay Bay). After some Yelp-ing, we decided to give Burger Bar a try.
We stopped in on a Tuesday night and we were seated right away. The booths have a small TV with their own channel controls. I tried flipping through the channels and it became quickly apparent that they only feature sports networks/shows. I'm not really a fan, but the TVs are a nice touch if you're into sports.
The menu has a selection of around a dozen specialty burgers, or you can pick your own toppings (and protein) to build your own burger. I opted for The Greek (lamb) burger. SOOOO ridiculously good. It had just the right amount of spice and the patty was cooked to perfection. The sandwich is served on a pita which makes sense but it does result in a slightly awkward meat-to-bread ratio. I can't have a decent burger experience without a beer so I was pleasantly surprised when I perused their beverage list. Their beer selection is fairly extensive with a lot of options from local breweries.