I got this one from a nursery school teacher friend many years ago. It was what she made for her "kids" for rewards! Rightly so! I had posted it at old TSR for someone looking for a soft sugar cookie that they could ship. This is what I posted.
These can be soft OR crisp. The key is to take them out AS SOON AS they start to puff up. For me it is about 8 minutes. You should do one cookie sheet first to test your oven for time. I have been making these for about 20 years and always mailed them to my kids in college cut out in appropriate shapes and decorated for major holidays - Valentine's Day as well as Easter, Halloween and Christmas. I wrapped two cookies at a time in Saran Wrap - backs touching each other so you don't mess up the icing. I packed them in the box with PLASTIC BAGS (from the grocery store!) on the bottom, between layers and tucked in all the corners. Most of the time they would make it without too many broken ones. In my sons' cases, they really didn't care if they were broken or not (Cookie Monster always said "Me LOVES Cookies!" and broke them on the way to his mouth anyway!)
3/4 cup butter
1 cup granulated sugar
1 teaspoon vanilla extract
2 1/2 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon salt
Cream butter and sugar together. Add eggs and vanilla extract and blend. Add remaining ingredients and blend. Chill at least one hour.
Roll dough onto flour surfaced and cut out into shapes. Bake on ungreased cookie sheet for 8 - 10 minutes at 350 degrees F.