Lumpiang singkamás is made primarily with julienned jicama, called singkamas in Filipino.
The crisp, pale root gives this lumpia its defining character. It is similar to lumpiang ubod, but the principal filling of singkamás is jicama rather than ubod, the tender inner shoot or heart of a coconut palm. The jicama is cut into thin strips so it cooks quickly and retains some texture.
Lumpiang singkamás may be served fresh or fried, depending on the recipe and local practice. That flexibility distinguishes it from some more narrowly defined lumpia varieties. Other ingredients can accompany the jicama, but they do not replace the root vegetable that gives the dish its name.
Jicama is also used in lumpiang sariwa and other Filipino vegetable fillings. It is easy to confuse singkamas with turnip because both are crisp roots, but they are different plants: jicama is a legume root, while the familiar turnip belongs to the mustard family.