I had an order of sushi the other night, and it was very good, but I cannot figure out for the life of me what was in the vegetarian maki rolls. I know there was avocado, but there was another (pickled) vegetable that was bright yellow and very crispy... any ideas?
The one you are asking about (in a Futomaki - I assumed) is a strip or shaved dried calabash bottle gourd (Ajitsuke kanpyou) that has been pickled. Here's a site you can check out:
Although, sometimes they use strip of pickled Daikon radish (also called White Radish, Japanese radish, Oriental radish, Chinese radish) - depend on the restaurants.