Decent, nice service size. It's just noodles and vegetables. It's from Noodle U. It's not on the menu but the man behind the counter speaks English. If you ask for the vegetable noodles that'll probably work. I showed him this vietnamese phrases I have on hand:
Tôi ăn chay thuần nghiêm, chỉ ăn rau củ. Tôi không ăn bất cứ sản phẩm động vật nào như trứng, sữa, phô mai, mật ong, nước mắm
纯素