Shortbread Cookies

Preheat oven to 300°F. Line 2 (8-inch) square or round cake pans with parchment and grease parchment.
Using a stand mixer and paddle attachment or electric mixer and a medium bowl, beat butter, vanilla, and sugar until fluffy, about 2 minutes. Add salt and flour, beating until just combined, about 2 minutes. Cookie dough will be stiff and a bit crumbly; add 1 teaspoon water while mixing if needed to bring dough together.
Divide dough in half and press into prepared cake pans, using your fingers or a greased piece of parchment to press dough into pans evenly. Using a paring knife, cut cookie dough into thirds in 1 direction, and into 1-inch pieces in the other direction. Prick dough all over with a fork. Bake shortbread until light golden brown, about 45 minutes.
Remove shortbread from pans and repeat cuts while still warm. Shortbread can be kept in an airtight container at room temperature up to a week, or longer in freezer.

Ingredient :

1 cup (8 ounces) unsalted butter, cold, cut into pieces
2 teaspoons vanilla extract
3/4 cup powdered sugar
3/4 teaspoon fine table salt
2 cups all-purpose flour