Start by measuring out all your ingredients.

In a mixing bowl, combine the egg yolk and Dijon mustard.

Begin adding the vegetable oil very slowly while whisking continuously.

Keep whisking until the mixture thickens and becomes creamy.

Mix in the lemon juice and white wine vinegar.

Add salt and cayenne pepper to taste.

If you want to add herbs, fold them in gently.

Transfer the mayonnaise to a clean container.