Source: http://www.dyannbakes.com/index.php?post_id=129091
Vanilla Shortbread
12 tablespoons (1 1/2 sticks) (=180 gr) of unsalted butter, softened
1/3 cup (=75 gr) of granulated sugar
1 tablespoon of pure vanilla extract
1 large egg yolk
1 1/2 cups ( 210 gr) of all-purpose flour
Chocolate Shortbread
8 tablespoons (1 stick) (=120 gr) of unsalted butter, softened
1/2 cup(=112,5 gr) of granulated sugar
1 teaspoon of pure vanilla extract
1 large egg
1 1/2 cup (=210 gr) of all-purpose flour
1/3 cup ( =27 gr) of Dutch processed cocoa powder (sifted after measuring)
1/2 teaspoon baking soda
1/8 teaspoon of table salt (not kosher)