Family Tested & Approved
Cream butter and sugar in mixer. Beat in eggs, vanilla, sour cream, soda, salt. Scrape sides and make sure well blended. Add flour a cup at a time, mixing well. Chill 20 minutes.
Roll out and cut into shapes. Only roll out dough 3 times, more than that and the dough becomes tough. Bake at 350 for 8-12 minutes until very light brown. Cool completely.