A vanilla bean is an extravagance that lends a note of sophistication to this drink, but extract is a fine substitute.

Ingredients

　　1 lb strawberries (1 qt), trimmed and halved (quartered if large)

　　1 cup fresh lemon juice

　　3/4 cup superfine granulated sugar

　　4 cups water

　　1 vanilla bean, halved lengthwise, or 1 teaspoon vanilla extract

　　Blend strawberries, lemon juice, sugar, and 2 cups water in a blender, 1 to 2 minutes (in batches if necessary). Scrape seeds from vanilla bean with tip of a knife into blender (or add extract), then blend with strawberry purée. If desired, pour through a very fine sieve into a pitcher to remove strawberry seeds, pressing hard on solids. Stir in remaining 2 cups water and serve over ice.

　　Cook's notes:

　　Cooler can be chilled, covered, up to 1 day. Vanilla pod can be placed in a jar of sugar to flavor it.