Recipe(tried): butter cookies and variation

Butter cookies
The mother of all butter cookies
Time: about 30 min or more if cookies are baked in batches
1 3/5 cu all purpose flour 3/5 c. cornstarch
3/5 c. sugar pinch salt
2 sticks chilled unsalted butter, cut into bits
1 t. vanilla extract 1 egg
3/5 c. milk, approx.
Preheat oven to 190C. Combine flour, cornstarch, sugar and salt in a food processor, and pulse once or twice. Add butter, and pulse 10 or 20 times, until butter and flour are well combined. Add vanilla and egg and pulse 3 or 4 times.
Add about half the milk and pulse 2 or 3 times. Add the remaining milk a little at a time, pulsing once or twice after each addition, until the dough holds together in a sticky mass.
Remove the dough from the machine to one or more bowls. You can make cookies from the variations below.
To make cookies, drop rounded teaspoons of dough (you can make the cookies larger or smaller, if you like) onto a non-stick baking sheet, a sheet lined with parchment paper or a lightly buttered sheet.
If you want flat cookies, press the balls down a bit with your fingers or the back of a spatula or wooden spoon. Bake 11 min, or until the cookies are done as you like them. Cool on a rack, then store, if necessary, in a covered container.
Yield: about 4 dz. Cookies.
Variations on the flavour of these butter cookies are limitless
* Butterscotch cookies: Substitute brown sugar for half or more of the white sugar, or simply add 1 tablespoon of molasses along with the egg.
* Citrus cookies: Omit the vanilla, and add 1 tablespoon of lemon or orange juice and 2 teaspoons grated lemon or orange rind along with the egg. A couple of tablespoons of poppy seeds can also be added.
* Chocolate chip cookies: Stir in about 1 cup of chocolate chips. (The butterscotch variation is good with chocolate chips.)
* Other chunky cookies:
To the finished batter, add about 1 cup of M&Ms (or similar candy), roughly chopped walnut, dried cherries or cranberries. Or combine any chunky ingredients you like.
*Spice cookies: Add 1 teaspoon ground cinnamon, 1teaspoon each ground all-spice and ground ginger and 1 pinch ground cloves and mace or nutmeg to the dry ingredients.
Or you can make rolled cookies by freezing the dough for 15 min or refrigerating it for at least 1 hour.
Working half the dough at a time, roll it out on a lightly floured surface; the dough will absorb some flour at first bit will soon become less sticky. Do not add more flour than necessary.
Roll about 1 inch thick, and cut with cookie cutters; decorate as you like. Bake as above, reducing the cooking time to 8-10 min.