I bookmarked Wandering Chopsticks' recipe for Tuong Ot Xa, or Lemongrass Chili Sauce, back when she first posted it. My serranos are extremely proliferative this year, and, at WC's suggestion, I used them for the sauce.
I started by mincing lemongrass, then finely chopping it, almost pureeing, in my spice grinder. Same with onion and garlic. Same with the fresh serranos, and the dried chilis de arbol (seeds removed).
(That's a bowl of ground-up chilis. Sorry for the blurriness and overexposure. Oh, and here's a tip - don't stick your face right over the grinder when you take the lid off.)
Saute it all up in a bunch of oil (I used mostly canola with a smidge of peanut), throw in your sugar, salt, fish sauce, and Sriracha, and let simmer for 10 minutes.
Either WC has an extremely high tolerance for pain, or I used some damn-hot chilis! However, it's soooo tasty. I can't wait to put it on absolutely everything.