This is a very simple way to preserve cherries that can later be used as pie filling. Just add some cornstarch mixed with a bit of water.
Wash and sterilize (boil in a canning pot with a rack for 10 minutes) three 500 ml mason jars. Keep the jars warm. In a separate pot, sterilize a funnel and ladle. 5 minutes before the cherries are ready to be added to the hot jars, boil the lids for 5 minutes.