Julia Child’s Secret for the Best Salad Dressing (It’s Already in Your Pantry)

One of the most fabled recipes in my family is a homemade mustard made from equal parts flour, Colman’s mustard powder, and apple cider vinegar. There is a batch made for almost every special occasion—Christmas roast to Easter ham would not be complete without the astringent, biting flavor. In fact, the recipe is so important to my family that my mother and sisters have a framed copy on display in their kitchens.

However, if I’m being honest (Mom, stop reading now!) I really don’t like it. The raw flour gives me the ick, and the combination of mustard powder and apple cider vinegar makes the flavor very acidic and out of balance. That said, I always have a jar of Colman’s mustard powder at home because it’s my family duty to be prepared to make the mustard at a moment's notice.

Recently, while enjoying a cup of coffee and leafing through Julia Child’s The French Chef Cookbook (as one does), I found another surprising use for that mustard powder. In her recipe for Sauce Vinaigrette, which she suggests using on green salads and French-style potato salads,

I noticed that she calls for 1/4 teaspoon of dry mustard instead of Dijon. I have to admit, while I usually blindly trust Julia, I was a little skeptical about this swap, but I decided to give it a try since I have a lifetime supply of the stuff.

How I Make Julia Child's Sauce Vinaigrette

I always make a quick-and-easy vinaigrette at the beginning of the week that I can use on salads, or to whip up a quick marinade on a busy weeknight. My go-to ingredients are good quality vinegar (white wine is my favorite), olive oil, salt, pepper, Dijon, and either minced shallot or garlic. Julia’s version is pretty much identical, minus the dry mustard swap and the addition of some dried herbs.

I tossed everything in a mason jar with a tight-fitting lid and shook it vigorously. To my surprise, it emulsified. (I always thought Dijon was the magic ingredient that created vinaigrette's creamy transformation, but it turns out that it’s just mustard in any form.) The pungent powder bridges the gap between the oil and vinegar, bringing them together in perfect harmony.

The resulting vinaigrette was smooth, clean, and peppery with none of the sharp, unpleasant flavors of my family's "famous" mustard. Now I'll just need to convince them that this is the new condiment we need at all family meals.