Ingredients
1 pound fresh strawberries, hulled (2 cups), plus more for serving
1 3/4 cups sugar
1 1/2 cups white-wine vinegar
3 tarragon sprigs, plus more for serving
Chilled seltzer, for serving
Preparation
In a medium nonreactive saucepan (such as stainless steel), combine strawberries with sugar and 1/2 cup water. Let stand, stirring a few times, 1 hour.
Cook over medium heat until warm to the touch, about 5 minutes. Add vinegar and continue to cook, stirring occasionally, until mixture comes to a simmer. Remove from heat and add tarragon. Let stand at room temperature, uncovered, 24 hours. Remove tarragon; strain mixture, discarding solids, and transfer to an airtight container. Refrigerate until cold, at least 1 hour and up to 1 month.
Fill glasses halfway with ice. Add 3 tablespoons shrub base and 6 ounces seltzer to each; stir once. Garnish with tarragon and fresh berries. Serve immediately.
