I love tom yum soup--the Thai soup that's usually offered with shrimp or chicken. I esp. like tom yum goong, the shrimp version. I've made it at home many times, but I always feel there's something missing. At my very good local Thai restaurants there's a film of red oil on top. What is that? It must come in a jar.
I'm going to move to a place that lacks good Thai food, so I'll have to learn how to make the version I love.