Add all ingredients except for olive oil to a blender. Blend on high until very smooth, 1 to 2 minutes. Add the olive oil, blend on low speed until just incorporated. Pour into a glass jar and store in the refrigerator until ready to use. Bring to room temperature before serving.
Note: I usually only use the shallot if I am using this recipe as a marinade for fish or chicken. It isn't really necessary for a salad dressing.
Recipe and featured image from http://www.nourishingmeals.com/2010/02/pepper-mint-dressing-marinade.html, retrieved 8/31/10.