Pulse peeled garlic cloves in the food processor 3-5 times until finely chopped but not a paste. Add salt and half the lemon juice, then process for 30 seconds to form a smooth paste.
1 cup garlic cloves, 1 teaspoon salt, 0.25 cup lemon juice
With food processor running on low speed, add the neutral oil drop by drop for the first 2 minutes to start a stable emulsion and thicken the mixture.
2 cups neutral oil
After incorporating the first third of the oil, add 1 tablespoon ice water. Continue alternating between a slow stream of oil and small increments of ice water until all oil and water are used, about 6-8 minutes total.
2 cups neutral oil, 0.25 cup ice water
Add the remaining lemon juice through the feed tube while the processor runs, and blend for 30 seconds more until fully combined and airy.
0.25 cup lemon juice
Taste and add more salt if needed, or thin with extra ice water if too thick. The sauce should resemble thick mayonnaise and have a bright white color without oil separation.
1 teaspoon salt, 0.25 cup ice water
