Separate the white from the yolk, reserve the yolk in a bowl. Add the spoonful of mustard, a drizzle of vinegar, salt and pepper.
Pierce your peeled garlic with a fork, then mix your products, always turning in the same direction and evenly.
Add the oil in a continuous stream, without stopping to turn. The mayonnaise should set after a few seconds. The amount of oil will depend on your mayonnaise needs.
Adjust the seasoning, if necessary.