Lottie Moon's Cookies

Do you know who Lottie Moon is? Lottie Moon was a missionary to China. While she was in China, she hosted small tea parties for girls. She made special, soft sugar cookies for them at her tea parties. Here is the recipe she used to make her cookies:
Ingredients:
1 1/2 cup of sugar
1/2 cup of sour milk*
1 egg + 1 egg white, beaten
1/2 cup butter
4 cups of flour
1/2 teaspoon baking soda
*Take 2 teaspoons of vinegar, then add milk to make 1/2 cup.
How to make it:
Preheat oven to 400 degrees. Cream butter and sugar, then add milk and eggs. Stir in flour to make a gooey dough. Lay dough on floured surface. Cut cookies 1/2 inch thin in circles or other shapes. Bake for 8-10 minuets or until light brown on top.