I found this on an email recipe list many years ago. These cookies are really wonderful. Here is a quote from the person who offered the recipe:
This recipe appeared about 30 years ago in Family Circle magazine. Cinnamon-sugar "frosts" the tops of these big old-fashioned puffs. They are soft and a bit cakelike and puff up high in the center. I have added chocolate chips to these sometimes, too and they were quite nice.They do puff up just beautifully. I didn't add chocolate chips this time.
Sour Cream Softies
3 cups sifted flour
1 tsp salt
1/2 tsp baking powder
1/2 tsp baking soda
1/2 cup soft butter
1 1/2 cups sugar
1 teaspoon vanilla
1 cup sour cream
Measure flour, salt, baking powder, and soda and sift together into a bowl.
In a separate bowl, cream butter with sugar until well blended.
Beat in eggs and vanilla.
Add flour mixture alternately with sour cream to make a thick batter.
Drop by by rounded spoonfuls onto greased cookie sheets.
Put a mixture of sugar and cinnamon in a little bowl, dip the bottom of a glass into it, and then flatten the cookie dough with it.
Bake in 400ºF oven 12 minutes, or until lightly golden around the edges.
Remove from cookie sheets and cool completely on wire racks.