Cream shortening, butter and sugar. Add eggs, lemon, vanilla and sour cream. Mix until well combined and smooth. Add sifted dry ingredients and mix until well combined.
Chill for several hours or overnight. Roll into balls and flatten with bottom of sugar coated glass or roll out and cut into shapes.
Bake at 350 degrees F just until the edges start turning color (7-10 minutes). Time will vary depending on how large and thick you made your cookies. It is important not to over-bake if you want the texture to remain chewy and soft. Frost and decorate as desired.