Reduction is aptly named. It's a technique that involves decreasing the volume of a liquid by boiling rapidly to cause evaporation. As the liquid evaporates, it thickens and intensifies in flavor. You can make a quick and easy sauce for meats and roasted vegetables by reducing stock or broth, wine, vinegar, or another liquid. The amount of reduction needed in a recipe usually is specified in one of two ways. A recipe may tell you to reduce a liquid by a general amount -- one-third or one-half, for example. Or, it may say to keep boiling until the liquid has reached a specific volume, such as 1/2 cup or 3 tablespoons. The size of the pan you use will affect the time it takes to reduce a liquid. A bigger pan has a larger surface area and results in faster evaporation. Be sure to use the pan size recommended in the recipe.