- Combine egg yolk, lemon juice, vinegar, mustard, and ½ teaspoon salt in medium bowl. Whisk until blended and bright yellow, about 30 seconnds.
- Add ¼ cup oil to the yolk mixture, a few drops at a time, whisking constantly for about 4 minutes. Gradually add remaining ½ cup oil in a very slow thin stream, whisking constantly, until mayonnaise is thick, about 8 minutes (mayonnaise will be lighter in color).
- Cover and chill. Can be made up to 2 days in advance. Keep refrigerated.
Variation: To make aioli, add 1 minced garlic clove to the egg mixture, and substitute extra virgin olive oil for the canola oil.