Preheat oven to 350 °F. In a small bowl, combine baking soda and vinegar; set aside. In another bowl, combine flour and spices; set aside. In a large mixing bowl, cream together butter, sugar and molasses until light and fluffy; beat in eggs. Gradually blend in flour mixture, baking soda mixture and sour cream. Drop by rounded measuring teaspoonfuls about 2 inches apart onto ungreased cookie sheets. Bake 10 minutes or until golden brown. Cool 1 minute on cookie sheet; place on wire cooling racks. Store in tightly covered container.