Instructions

1. Add 1 part vinegar to a mixing bowl. Use 1/4 cup of vinegar for every 1 cup of light vinaigrette you want to make.

   Champagne and white-wine vinegar, which are light in color and tartness, fit the description of "light vinaigrette" closest, but you can choose from other light vinegars as well. For example, to temper watercress's peppery bite, consider a sweet vinegar, such as apple cider, or a fruit-based variety, such as elderberry or sour cherry. To bring out watercress's floral qualities, use an herb-infused vinegar, such as tarragon or rosemary.

2. Add a small spoon of dijon mustard to the vinegar and whisk until incorporated. Dijon mustard is to vinaigrette what the lecithin in egg yolks is to hollandaise -- an emulsifier. Dijon emulsifies the oil and vinegar and keeps the vinaigrette stable after you mix it.

3. Add soft fresh herbs to the vinegar and dijon. Most aromatic herbs soften watercress's peppery bite without masking it. Thyme, parsley, tarragon, chervil and sage all work with watercress and light vinaigrette. Add a pinch of salt and whisk until it dissolves.

4. Drizzle 3 parts neutral oil into the vinegar and mustard slowly, whisking vigorously while you pour. Place a moist, folded paper towel under the mixing bowl to keep it stable so you can drizzle and whisk at the same time. Neutral oils include light olive, sunflower, safflower and peanut.

5. Dip a few leaves of watercress in the vinaigrette and shake off the excess. Taste the vinaigrette and determine if it needs more vinegar, herbs or salt. Adjust the vinaigrette as needed and store it in the refrigerator for at least 30 minutes.

6. Add the cleaned and dried watercress to a mixing bowl and whisk the vinaigrette. Pour a tablespoonful of vinaigrette around the sides of the mixing bowl, not directly on the watercress.