Toum (Garlic Sauce)

Crush garlic cloves using mortar and pestle until smashed and softened, about 20 seconds. Transfer to food processor, and process until finely chopped, about 10 seconds, stopping to scrape down sides as needed. With processor running, slowly pour in 1/4 cup oil, pouring in a thin, even stream, processing until well blended, about 2 minutes, stopping to scrape down sides as needed.  

With processor running, gradually add 1 tablespoon lime juice to garlic mixture, processing until incorporated, about 20 seconds. With processor running, add egg white, processing until well combined, about 30 seconds. With processor running, gradually stream in remaining 3/4 cup oil, processing until mixture is thick and fluffy, about 2 minutes. With processor running, gradually add remaining 1 tablespoon lime juice, processing until incorporated, about 20 seconds. Add salt and, if toum is very thick, add cold water, 1 teaspoon at a time, to thin into a smooth and spreadable consistency, pulsing 3 to 6 times after each addition. Add additional salt to taste.