As is common outside of Las Vegas, many of the poker rooms here will offer tableside dining, so you don't have to leave the game. We called a few rooms and here's what we found:
However, when it comes to tableside dining outside of the poker room, we know of only two Las Vegas casinos that offer this service. One, as you correctly point out, is the El Cortez downtown, which has been feeding gamblers since March, 2007. Their "Gourmet Gambler" menu is available to all players -- pit and slots -- and features a selection of items from the coffee shop, with an automatic $1 discount on the regular price. You can pay with cash, chips, or points, and if you use the latter, you can receive additional discounts, up to 75%. Even better, the helpful member of the pit staff that we spoke to told us that the food served tableside is better than what you get in the coffee shop because the portions are bigger. So, more food and it's cheaper. Sweet! To the best of our knowledge the Gourmet Gambler menu's available from 10 a.m.-11 p.m. daily, but check with the pit.
The other casino to offer this service is Palace Station, which introduced tableside gaming to its Asian pit in October, 2006. Today, from what we understand, it's now limited to the baccarat pit and the menu comes from the new Chinese Food Express franchise on property. There's a dedicated server available from 6 p.m. until 2 a.m. daily to take your order.