My Mom's Shortbread. Line 2 cookies sheets with parchment paper.
Beat butter until creamy about 3 minutes. Sift icing sugar, corn starch, salt and flour 4 times (I know, but it is worth it). Add the dry sifted ingredients to the creamed butter a little at a time and work in with a wooden spoon as long as possible*, then move to a lightly floured flat surface and knead until the dough cracks slightly.
Roll gently with a lightly floured rolling pin to 1/3" (1 cm) thickness or pat to desired thickness with the palm of your hand. Cut out with Christmas cutters and place on the prepared cookie sheets, bake for approximately 10-12 minutes, don't let them brown. Let cool on cookie sheets, then move to a wire rack.
My friend's Shortbread
Cream butter until fluffy, add sugar and cream together, then add the flour gradually and mix with a wooden spoon* as much as you can. Move the mixture to a lightly floured flat surface and with your hands work the dough until it comes together and forms a ball. If it is too sticky, wrap in plastic and refrigerate for approximately 30 minutes. On a lightly floured surface roll to 1/3 inch (1 cm) thickness. Cut out with desired shapes, place on prepared cookie sheets and bake for approximately 10-12 minutes. Let cool on cookie sheets and then move to a wire rack.
** I have received a couple of messages saying my Mom's shortbread doesn't come together and they had to add butter, a lot of butter! So I just made it again and no extra butter is needed, please note this is a dough that needs to be kneaded not whipped and don't forget the sifting. It will be crumbly until you start to knead it, then with a little bit of elbow grease you will arrive at the desired dough. Or you can also bring it together with a stand up mixer. Hope this helps. Let me know. Rosemary
*or use the paddle attachment on the mixer until almost combined.
If you use unsalted butter add 1/4 teaspoon of salt.