How to Make It
In a steamer basket, steam the leeks over boiling water until tender, about 10 minutes; pat dry. Arrange the leeks on salad plates or a platter.
In a medium bowl, combine the sherry vinegar with the truffle juice, balsamic vinegar, a pinch of sugar and a generous pinch each of salt and white pepper. Gradually whisk in the oils. Pour the vinaigrette over the leeks. Thinly shave the truffle over all and serve immediately.