Half Moon Cookies (Black and White Cookies)

1 cup sour milk or buttermilk
1 & 1/2 cups sugar
3/4 cup shortening
2 eggs
1/2 teaspoon salt
3 cups flour
1 teaspoon baking powder
1 teaspoon baking soda
1 or 2 teaspoons vanilla essence

Cream sugar and shortening; add eggs. Beat well.
Sift together flour, baking powder and salt.
Stir baking soda into sour milk.
Add milk alternately with the flour to the creamed mixture.
Add vanilla essence. Mix in well.
Drop by rounded teaspoons onto greased cookie sheets.
Bake at 350*F (180*C) for about 10 minutes, until tops are set.
Cool on wire racks.
When cool, frost half of cookie with chocolate, and the other half with vanilla frosting.