This comes from the Joy of Baking website. There is an extensive set of instructions on the website, but here are the basics.
2 cups (260 grams) all-purpose flour
1/4 teaspoon (2 grams) salt
1 cup (2 sticks) (226 grams) unsalted butter, room temperature
1/2 cup (60 grams) powdered (confectioners or icing) sugar
1 teaspoon (4 grams) pure vanilla extract
Shortbreads: In a separate bowl whisk the flour with the salt. Set aside.
In the bowl of your electric mixer (or with a hand mixer), beat the butter until smooth and creamy (about 1 minute). Add the sugar and beat until smooth (about 2 minutes). Beat in the vanilla extract. Gently stir in the flour mixture just until incorporated. Flatten the dough into a disk shape, wrap in plastic wrap, and chill the dough for at least an hour or until firm.
Preheat oven to 350 degrees F (177 degrees C) with the rack in the middle of the oven. Line two baking sheets with parchment paper.
On a lightly floured surface roll out the dough into a 1/4 inch (.6 cm) thick circle. Cut into rounds or other shapes using a lightly floured cookie cutter. Place on the prepared baking sheets and place in the refrigerator for about 15 minutes. (This will firm up the dough so the cookies will maintain their shape when baked.) Bake for 8 -10 minutes, or until cookies are very lightly browned. Cool on a wire rack.
For Chocolate Dipped Shortbreads: Place 3 ounces (90 grams) of the finely chopped chocolate in a heatproof bowl and place it over a saucepan of simmering water. Once the chocolate has melted, remove it from the heat. Add the remaining chocolate and stir with a wooden spoon until it has completely melted and is smooth and glossy. Taking one cookie at a time, dip one end of each cookie in the melted chocolate and place it on a parchment lined baking sheet. Once all the cookies have been dipped in the chocolate, place the baking sheets in the refrigerator for about 10 minutes, or until the chocolate has hardened.
Shortbread cookies with keep in an airtight container for about a week or they can be frozen.
Makes about 20 shortbread cookies.