The amount of water necessary to make pastry dough is likely to change slightly from time to time, depending on variables such as humidity and the moisture content of your butter and even, believe it or not, your flour.
Ingredients
2 1/2 sticks (1 1/4 cups) cold unsalted butter
3 1/4 cups all-purpose flour
1 teaspoon salt
1 1/4 cups well-chilled sour cream
4 to 6 tablespoons ice water
Directions
Cut butter into 1/2-inch cubes.
In a bowl with your fingertips or a pastry blender blend together flour, butter, and salt until most of mixture resembles coarse meal with remainder in small (roughly pea-size) lumps. Stir in sour cream with a fork just until incorporated. Drizzle 4 tablespoons ice water over mixture and gently stir just until incorporated. Test mixture by gently squeezing a small handful: When it has proper texture it should hold together without crumbling apart. If necessary, add enough remaining water, 1 tablespoon at a time, stirring until incorporated and testing, to give mixture proper texture. (If you overwork mixture or add too much water, pastry will be tough.)
In a food processor pulse together flour, butter, and salt until most of mixture resembles coarse meal with remainder in small (roughly pea-size) lumps. Add sour cream and pulse just until incorporated. Drizzle 4 tablespoons water over mixture and pulse just until incorporated. Test mixture by gently squeezing a small handful: When it has proper texture it should hold together without crumbling apart. If necessary, add enough remaining water, 1 tablespoon at a time, pulsing until incorporated and testing, to give mixture proper texture. (If you overwork mixture or add too much water, pastry will be tough.)
Turn mixture out onto a work surface and divide into 4 portions. With heel of hand smear each portion once in a forward motion to help distribute fat. Gather dough together and form it, rotating it on work surface, into a disk. Chill dough, wrapped in plastic wrap, until firm, at least 1 hour, and up to 1 day.
