He Luo are buckwheat noodles made using a traditional wooden press — a large lever mechanism that forces the dough through a perforated plate directly into boiling water. The noodles emerge thick, dark, and wonderfully chewy with buckwheat's distinctive earthy, nutty flavor. In Xi'an, they're most often served cold, topped with a dressing of chili oil, black vinegar, garlic, sesame paste, and fresh cilantro. The cool, firm texture of the noodles combined with the pungent, tangy dressing makes for a refreshing and satisfying dish — especially popular in summer months.
This noodle-making technique originated in the mountainous regions of Shaanxi where buckwheat grows well. The wooden press method was developed in the Tang Dynasty and has remained largely unchanged for over 1,000 years. The 'he luo' press itself is considered a cultural artifact.