Mash berries, 2 cups at a time with potato masher

Cook berries in medium pan, until juices are flowing

Remove from heat and run mixture through strainer to remove pulp

Cook berry juice in medium pan, until boiling, stirring occassionly

Add sugar & cornstarch

Stir constantly & bring back to full boil

Boil for 1 minute stirring constantly

Remove from heat & ladle into hot 1/2 pint jars

Clear top of jars edges, add lid seals

Put on rings and tighten

Add to large canner pot with hot water.

Water should cover jar tops by 1"

Boil for 10 minutes

Let cool in canner if you are only doing one batch

Once cool, remove jars from canner and check that lids are sealed. (when you press on center of lids they should not make a pop sound).

If one is not sealed you can reheat in canner to get it to seal.