In a food processor, pulse the cherries, in batches, until very finely chopped; transfer the cherries and their juices to a very large high-sided skillet.

Add the pectin and whisk well to combine.

Bring to a rolling boil over high heat, stirring often.

Add the sugar in one addition, whisking to combine.

Return to a steady boil, stirring often, and cook for one minute.

Remove from the heat and, using a large spoon, skim any foam off the top and discard.

Pour the jam into sterilized mason jars, leaving ¼” headroom.

Wipe the rims to remove any jam, if necessary, place the lid on top and hand-tighten the screw cap.

Process in boiling water for 15 minutes before transferring to a cooling rack for 2 hours. Refrigerate any jars that do not properly seal.

Store in a cool, dry place for up to a year; refrigerate once opened.