Oc luoc xa is a traditional dish originating from the Ninh Binh region. It's made with mountain snails which live on the limestone mountains in Tam Diep town. The snails appear only from April to August, making this dish a seasonal delicacy. The texture of the meat is tough and brittle.

Although there are a few dishes made with these snails, they're most commonly boiled with spices such as lemongrass, ginger, and red chili peppers. Once prepared, the dish is traditionally accompanied by fish sauce for dipping on the side.