Subash Yadav's food draws from both north India and Nepal, the countries of his parents, crossing the border as freely as his truck crosses the Valley. His most popular plate? The momo, a rarity in this part of the world. Yadav fills his Himalayan dumplings with chicken, beef, or vegetables. They are lavishly spiced with ginger, turmeric, and other warm flavorings. The sloping walls of these Nepali-style dumplings are thick and rich, and disclose hot, tender interiors, plus intense flavors lengthened by cilantro and chile sauce. Be sure you order these should you spot the blue-and-white truck, and be sure to round them out with Yadav's other memorable offerings, like mango lassi with cardamom and saffron. Yadav is just getting started. He's looking to expand his menu — and his momo styles.