Using the pairing knife, split each garlic clove in half lengthwise. With the tip of the knife, remove the germ from every clove.
Place garlic cloves and salt in the bowl of the food processor. Pulse garlic in short bursts until finely minced, scraping down the bowl occasionally with a spatula. Add 1 tbsp lemon juice and process until a paste forms. Add another 1 tbsp of lemon juice until completely smooth and slightly fluffy. This can take up to 15 minutes.
With the processor still running, slowly drizzle in 1/2 cup of grape seed oil in a very gentle stream, followed by 1 tbsp of lemon juice. Continue to process until liquids are completely incorporated. Repeat with another 1/2 cup of grape seed oil and remaining 1 tbsp of lemon juice.
Continue the process, alternating 1/2 cup of grape seed oil and 1 tbsp ice water until all of the oil and water have been incorporated. (4 more times). It is best to keep track of the number of times you have added the grape seed oil and ice water.
Toum can be stored in a jar for up to 3 weeks to a month before it will start to separate.