Cover ⅔ glass of cranberries with a little water, add ½ vershok stick cinnamon, and bring to a boil. Strain, beating with a spoon. Add sugar to 2½ glasses of this juice and bring to a boil. Cool and pour over the pudding. Or, add 2 teaspoons potato flour mixed with 1 spoon water and bring the sauce to a boil, stirring briskly for 3–4 minutes. Pour over the pudding and serve the remainder in a sauceboat.