Preheat oven to 375°F (190°C).

In a large bowl, beat sugar and shortening together until light and fluffy.

Add eggs and mix well.

In a separate small bowl, dissolve soda in sour milk.

Add vanilla to the sour milk mixture.

Gradually add the sour milk mixture to the sugar and shortening mixture.

In another bowl, stir together flour and baking powder.

Slowly incorporate the flour and baking powder mixture into the wet ingredients.

Drop by rounded spoonfuls onto a greased cookie sheet.

Bake for 12 to 15 minutes, or until golden brown.

Let cookies cool on the baking sheet for a few minutes before transferring to a wire rack to cool completely.