1. Mash together until a paste is formed garlic and salt.
2. Remove to bowl or jar with a tight-fitting lid. Whisk or shake in until well blended red-wine vinegar or fresh lemon juice, Dijon-style mustard and salt and ground black pepper to taste.
3. Add in a slow, steady stream, whisking constantly, or add to jar, shaking until smooth, extra-virgin olive oil. Use at once or cover and refrigerate.