One One Dumpling in San Gabriel is definitely a hidden gem in the SGV. This small and unassuming restaurant may be easy to miss, but its delicious food is worth the effort to seek it out. As mentioned in other reviews, the hours can be a bit tricky to navigate, so make sure to plan ahead before you go. The menu is simple, with only two categories: dumplings and noodle soup. But don't let the simplicity fool you - the quality of the food is outstanding. The chive and pork dumplings are a standout when fried, with the perfect combination of flavors and textures. For those who prefer boiled dumplings, the cabbage and pork is a great option. The chili oil that comes with the dumplings is tasty, though some may prefer it to have a bit more umami flavor. If you're in the mood for something warm and comforting, the noodle soups are also a great option. The beef tendon soup is a popular choice, with a simple and clean broth that complements the tender and flavorful beef tendon. The atmosphere of the restaurant is cozy and intimate, with only about 20 seats available. It definitely has a mom-and-pop shop feel, which adds to the charm. Service is friendly and efficient, and the prices are very reasonable - though you'll need to have cash. Just make sure to check the hours and plan accordingly, as it's definitely worth the effort to try.