After salt, acid is the next most important ingredient in seasoning a dish. Acid most commonly comes in the form of vinegar or citrus juice. Acid can be added at the end of the cooking process to add a certain brightness to the dish or to cut through richness, for balance. We like to add a tiny squeeze of lemon to most things we cook. And as far as vinegar goes, Sherry vinegar is by far our favorite. It has a great depth of flavor, and it makes the most delicious vinaigrette.