This heirloom cookie was originally made with homemade sour cream stored in a crock in the basement. The dough for drop cookies is soft enough to drop from a spoon. Use an ordinary teaspoon rather than a measuring spoon. Use slightly rounded spoonfuls rather than level ones. Push the dough off the spoon with a rubber spatula or another spoon. Make the drops all the same size so they will bake evenly. Bake them just until done. Remove immediately from baking sheet. If cookies are left for only a few minutes on a hot sheet, they will continue to bake and will be overdone and dry.