This is a sauce worth mastering, as freshly made mayo is so good. For a lustier mayo, substitute half of the canola oil with your best olive oil. Be sure to have all your ingredients at room temperature. The whole key to making mayo is forming a stable emulsion -- the marriage of the egg yolks and oil -- first. To do this, you need to add the oil very, very slowly in the beginning -- no more quickly than about a tablespoon at a time. Once a thick emulsion has been established -- when it starts to look like mayo -- you can add the oil a little more quickly. But as a frequent victim of broken mayos, I like to continue adding it slowly. If it does break on you, don't fret: You can fix it. A note at the bottom tells you how.
Makes about 1 cup
2 egg yolks, at room temperature
2 teaspoons Dijon mustard
1/2 teaspoon sea salt
pinch of finely ground white pepper (optional)
2 teaspoons white wine vinegar or lemon juice
1 cup canola oil
Place the egg yolks, Dijon mustard, salt, pepper and one teaspoon of the vinegar or lemon juice in a medium bowl. Using a hand mixer, whisk them together on low speed until they're smooth.
Start adding the oil, while continuously beating the mixture on medium speed -- adding no more than a tablespoon at a time. Wait for the the oil to completely combine with the yolk mixture each time time before adding the next tablespoon.
Once the mixture is thick and mayonnaise-like, you can add the oil a little more quickly. Continue until all of the oil is incorporated. Beat in the second teaspoon of vinegar or lemon juice, taste the mayo and add more salt if needed.
How to repair broken mayo
If at any point during the above process, the mayo "breaks" -- that is, the oil separates out, you can fix it. Just stop, put a fresh (room temperature) egg yolk into a clean bowl, then beat the broken mixture a tablespoon at a time into the egg yolk.