My LA discovery of the year is Chong's Grocery. A tiny little storefront in Koreatown, Chong's makes its own sesame oil! And it's fantastic! I had no idea fresh sesame oil could taste so alive. No hint of rancidity at all. Chong's sells both light and dark oil in a variety of bottle sizes. I got the smallest, a 16 ounce bottle for $10, which is a bargain. They also have toasted sesame seeds, barley, soy beans, etc.
Warning: if you're trying to find the store, please be aware that they're on the phantom 8th street. Phantom 8th street, you ask? Yes. Because, it turns out that there are two 8th streets: the main 8th street and a tiny side street that parallels it for about a hundred feet which is also called 8th street. Chong's is on that parallel side street.
3560 W 8th Street
213 387 0651
BTW, according to the Korean spelling, the store should really be called Jeong's Grocery. Just saying.