1. To make the mayonnaise by hand, place the egg yolks, lemon juice, vinegar, mustard, salt, and pepper in a medium bowl. Stabilize the bowl by nestling it in a damp kitchen towel. Using a wire whisk, whisk until the mixture is smooth and the ingredients are incorporated. Then whisk in the oil, a few drops at a time to start, until the mayonnaise starts to come together and thicken.
2. As the mayonnaise thickens, continue to whisk the oil into the bowl in a very thin stream to ensure a creamy mayonnaise. If you add the oil too quickly, the mixture will not thicken. Whisk vigorously to make an emulsion. You can stop for a moment to rest your arm or switch hands, if needed. Go slowly, continuously whisking until all the oil is used and the mayonnaise is thick and creamy. Taste the mayonnaise and add salt, pepper, or more lemon juice, as needed to suit your taste.
3. To make in a blender, whisk the yolks, lemon juice, vinegar, mustard, salt, and pepper together in a small bowl until smooth. Place the mixture in the blender and blend on low for a few seconds. Very, very slowly, begin to add the oil, a few drops at a time. When the mayonnaise begins to thicken, add the oil in a very slow, steady stream until all the oil is incorporated. Add more salt, pepper, or lemon juice, as needed for your taste. (Tool tip: If you’re using a blender, a long, thin, flexible silicone spatula makes getting all the mayonnaise out of the blender easier).
4. To store, place the mayonnaise in a small glass container with a tight-fitting lid and refrigerate for up to 4 days. If the mayonnaise gets too thick, whisk in 1 to 2 teaspoons warm water to thin.
Eat Fat, Get Thin recipes courtesy of Little, Brown and Company.