It couldn't be easier, and thanks to the mustard, it's creamy and stable. As a bonus, any leftovers are conveniently ready to be stored for the next salad.
It doesn't have to be red wine vinegar, of course. You can use any type of acid, like lemon juice or another type of vinegar. And it doesn't even have to be mustard -- though you do need an emulsifying agent to help incorporate the oil. Mom used to make a French dressing by combining equal parts of ketchup, vinegar, and oil in a jar, along with pinches of salt and cayenne pepper. We make another dressing that's just tahini, oil, and lemon juice, shaken in a jar. And of course, you can add any herbs or seasonings that you'd like.
Perhaps this "method" holds a special place in this writer's heart, as doing the shaking was one of the first ways she got to be "helpful" in the kitchen. Mom was a smart cookie, after all. She got her salad dressing made, and used up some endless kid energy in the process.
Related: Recipe: Raspberry Vinaigrette
(Image: Nina Callaway)