Preparation 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.
Preparation 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.