Soft, puffy, and slightly crinkly, these classic snickerdoodles deliver sugar ‘n’ spice all year ’round, not just at Christmas. But there’s no escaping that bit of Yuletide in this snickerdoodle. It is one of the irresistible treats my sister-in-law Chris heaps upon her splendid Christmas cookie tray. And Chris got this recipe from “Sister Santa Claus.” It goes back to Chris’s sophomore Home Economics class at Cathedral High School in Springfield, Massachusetts. Many of the nuns who taught her had a male name along with a female one—such as Sister Mary Timothy. So I took her literally when she mentioned Sister Santa Claus. “It wasn’t her real name, but we called her that because…