In Korea, tteokbokki (tech-boke-ee) comes in many guises. The ubiquitous street-food version consists of rice cakes floating in a sweet-spicy sauce made with corn syrup and gochujang (Korean chile paste). This take, served in only one particular market in Seoul, was the simplest and most delicious I had--crisp on the outside and chewy within. You'll find rice cakes for tteokbokki at Korean markets; they're about the size of a thumb. There really is no substitute for gochugaru (Korean ground chile). It's earthier and far less spicy than many other ground chiles.