Combine the rosemary, garlic and olive oil in a blender or food processor. Process until the rosemary is finely ground.
Transfer to a smaller vessel with a spout and reserve.
In a large bowl, whisk together the egg yolk* and the salt. Note, the more wires your whisk has, the easier it will be to make this mayonnaise. Whisk in 1 teaspoon of the lemon juice.
Add a few drops of the rosemary olive oil and whisk briskly. Repeat, adding a small amount of olive oil each time. Once you have added 1/3 of the olive oil, add another teaspoon of the lemon juice. Continue adding olive oil a few drops at a time and whisking until 2/3 of the olive oil has been added. Whisk in the remaining lemon juice. At this point, you can pour a thin stream of the olive oil while whisking constantly. It helps to have someone do the pouring while you do the whisking. When finished, you should have a smooth and stable mayonnaise texture. However, it can separate after a time. Cover and refrigerate, and use it within 1 hour.
*There is a slight risk of salmonella or other food-borne illness when consuming raw eggs. Use caution. Use only fresh, clean grade A or AA eggs. Avoid contact between the yolks or white and the shell. Do not use the shell to separate the yolks. When available, use pasteurized eggs.
- 1 cup extra virgin olive oil
- Leaves/needles from 3 sprigs rosemary
- 1 large clove garlic, peeled
- 1 egg yolk*
- 1 teaspoon fine sea salt
- 3 teaspoons freshly squeezed lemon juice