I use a high quality vinegar, like the O California oak aged balsamic vinegar or even the fig balsamic from the same brand (I have no affiliation with them, I just enjoy their products!). I also use a nice olive oil; I source my olive oil from small, local gourmet shops; my favorites are organic olive oil from small producers in Greece, Argentina, and Chile. I like using fine grey sea salt from France, or a nice seasoned salt.