As an East Coast resident, the first thing I do when in LA upon landing is go straight to In N Out Burger - it's the best burger you will ever have! I really wish they would expand into Florida, they would make an absolute killing - sooo many people here love them and crave them! Try one - and you will be a dedicated fan, also!
Favorite Dish: Double Double burger, and a chocolate shake!
In-N-Out Hamburgers! They are the best. They are all family owned and have not changed the menu since 1948. It is burgers, fries, sodas, and milkshakes. Period, no more, no less. The burgers are not big but they are 'Hot and Fresh'.
They have remained true to their origins and are overwhelmingly popular in SoCal.
Favorite Dish: The Double-Double. Two patties and two cheese slices. About as big as a Big Mac but mucho tastier!
L.A. is a big flat expanse of real estate; drive in any direction and you will encounter Fast Food. Jack In The Box, Carl's Jr., Taco Bell, McDonald's, In & Out Burger, Burger King, Kentucky Fried Chicken. A more local style of Fast Food is Tommy's Original Burgers, laden with cheese and chili. If you miss your turn keep driving and there will be another fast food joint in no time. Ditto for gas stations and convenience stores.
Favorite Dish: Hamburgers, cheeseburgers, burritos, tacos, you name it. Favorites include Jack In The Box, 2 tacos for 99c; Chicken Club from Carl's Jr. Whopper from Burger King.
For fast food: In n Out Burger
Favorite Dish: The whole menu consists of 3 different burgers, fries, shakes and soft drinks. Not much but they've got this stuff down.