Vanilla is prized for its ability to bring subtle changes to many recipes. Though this recipe uses frozen lemonade concentrate as a shortcut, Fred Thompson, author of the cookbook "Lemonade," doesn't recommend cutting corners on vanilla: use vanilla beans for the most unadulterated vanilla flavor, or pure vanilla extract.

Ingredients:

12-ounce can frozen lemonade concentrate, thawed

6 cups cold water

1/3 cup sugar

¼ teaspoon kosher salt

2 vanilla beans or pure vanilla extract, to taste

2 large lemons, quartered and seeded

Method:

In a 3-quart pitcher, combine the lemonade concentrate, water, sugar and salt. Stir until the sugar is dissolved. If you are using vanilla beans, split the beans lengthwise down the middle and scrape out the seeds into the lemonade mixture. Discard the beans. Stir until the seeds have separated. Alternatively, add vanilla extract to taste. Let the lemonade steep for at least 10 minutes. Strain the lemonade, if desired, through a fine-mess strainer to remove any vanilla bean residue. Squeeze each lemon wedge into the pitcher, then add the rinds. Chill until very cold and serve in tall glasses over ice. Makes 2 quarts.

Recipe from Fred Thompson's "Lemonade," Harvard Common Press, 2002