1/4 cup white wine, Champagne, or aged Sherry wine vinegar
2 teaspoons Dijon mustard
1 teaspoon kosher salt
Freshly ground black pepper
2/3 to 3/4 cups extra-virgin olive oil
In a small mixing bowl, whisk together the vinegar, mustard, salt, and pepper. Gradually whisk in enough oil to make a smooth dressing with a balanced taste. Use immediately or store covered, in the refrigerator, for up to 1 week.