Drain cherries into a measuring cup, saving juice. Pour 1/2 cup of Kirsch over drained cherries in a bowl, mix and leave aside for an hour or overnight. Drain the soaked cherries into the first cup with juice. You will have a total of about 2 cups juice. Take a few tablespoons of this juice and put in a cup. Add 2 tbsps cornstarch and make a smooth slurry. Pour the 2 cups juice into a saucepan and bring to a boil. Add cornstarch slurry and cook 1 minute. Set aside to cool. Put aside 12 cherries. Put remaining cherries in a bowl and add 3 tbsps of the cooled, thick cherry sauce, mix well. Save the remaining sauce for another use.