Place the eggs, mustard and salt in a regular or immersion blender.
If you use an immersion blender, make sure that before you start mixing the blender is at the bottom of the container.
Mix all the ingredients at low speed until everything is well incorporated (less than 1 minute).
Start pouring the oil in a thin, constant stream while continuing to mix. This is key to achieving the right emulsion for a good mayonnaise. Stop adding the oil when you have achieved the desired consistency.
To the blender, add the garlic and vinegar, mix everything until you don't see any pieces of garlic, taste and adjust flavors. Don't miss the salt and pepper.
Store it in a sterilized container in the refrigerator for up to a week.