Gather all the ingredients and a narrow, tall mixing jar (a measuring cup works excellently for this purpose). Pour all the ingredients into the mixing jar.
Insert an immersion blender to the bottom of the jar. Blend the ingredients on high speed. Resist moving the blender until the eggs and oils have emulsified from the bottom all the way to the top.
After achieving the initial emulsification, gently move the blender up and down within the jar until the mixture reaches a creamy mayonnaise consistency.
Transfer the mayonnaise into a storage jar. The fresh mayonnaise can be stored in the refrigerator and will remain fresh for about 4 days (it can last for up to one week but use your judgement).