Pad Thai uses rice noodles; what are their two principal ingredients?

Rice noodles have rice flour and water as their two principal ingredients.

The flour is made from rice, which is ground and processed into a starch-rich base. Water hydrates that flour and allows it to be formed into strands, sheets, or other noodle shapes. Some recipes and commercial products add tapioca starch or corn starch to improve transparency, elasticity, or chewiness, but those are supplemental ingredients rather than the principal pair.

Rice noodles are common across China, India, and Southeast Asia. Their forms vary widely, from thin rice vermicelli to broad flat noodles such as those used in several stir-fries and soups. Fresh, frozen, and dried versions are all available.

A frequent mistake is confusing rice noodles with wheat noodles. Wheat noodles contain wheat flour and develop a different texture because of gluten; rice noodles are naturally gluten-free when no other ingredient introduces gluten.

Historical accounts often connect the development of rice noodles with southern China, where rice was better suited to the climate than wheat. Their techniques later spread widely through Asian cuisines.