Hudson's grill is a fun, casual place to eat when you are in San Luis. It's styled after a 1950's burger joint. They have really good burgers and some yummy curly fries that they serve in a basket together. One of the things that the kids like to see is the car that is "crashed" through the wall. They are famous for their milkshakes - served the old fashioned way in a tall glass with whipped cream and a cherry and the rest of the shake served next to it in a metal shaker.
For the adults, they have some really good HUGE margaritas for a pretty cheap price and they have lots of flavors to choose from.