Place the egg yolks in the blender jar and pulse until mixed. Add the salt, mustard and 2 teaspoons lemon juice. Select Auto 3 and slowly add the oil through the pour spout as the blender is running. As the mayonnaise emulsifies, it will thicken.
When thick and smooth, taste and adjust seasonings as desired. Add remaining lemon juice according to your preference. Store in the refrigerator in a tightly sealed container. Keeps for about 1 week.