This gorgeous oil is wonderful made with any herbs you love, including mint or dill or tarragon, or a combination. Drizzle the oil on a dish and eat with bread or vegetables; it's also great on crostini, eggs, labneh, soups, and anywhere you can think of! Store the oil in a jar in the refrigerator; it will last a good month or more. Use the herb puree that is left from straining, stirred into sauteed spinach or in vinaigrettes.
Make an ice bath in a large bowl with several cups of ice and a couple of cups of water. Set aside.
In a medium saucepan, bring a couple of quarts of water to boil. Plunge the basil and the garlic in the boiling water for about 15 seconds, then transfer the basil immediately to the ice bath. Set the garlic aside.
Once the basil is chilled in the ice bath, transfer the basil to a clean towel and wring out as much water from the basil as possible.
In a high-powered blender, combine the basil, garlic, salt and oil. Blend on high speed for about one minute, then a second time for about a minute.
Line a strainer with a layer of paper towel or a couple of layers of cheesecloth, and place the strainer over a bowl. Pour the blended oil into the strainer, and allow the oil to strain for a good half hour.
Pour the oil from the bowl into a jar; taste and add salt if needed. Use the remaining pureed herbs in some other dish that will be more delicious because of it.