Prepare sterilized jars to manufacture specification, keep water and jars on stove over medium heat.

Wash plums in cold water

Remove pits

Leave skin on

Cut plums into fourths

Add plums, lemon juice and water to a large stock pot, cook over medium high heat until boiling

Strain mixture through a rough sieve to remove skins (optional)

Return liquid to stock pot, add sugar, stirring constantly, bring back to a rolling boil (a boil that stirring cannot break)

Add pectin, stirring constantly, bring back to a boil and cook for 1 minute

Let rest 1 minute and skim foam using a spoon or spatula

Test jell point: In a medium bowl pour ice cubes then add ice water leaving an inch head space

Rest a metal measuring cup on the top of the cold water

Place a tablespoon hot liquid in cold measuring cup, wait about a minute and test the jell, if the jell is to soft, return mixture to the stove and cook additional 1 minute

Ladle hot liquid into sterilized jars, clean rims with a damp cloth, place lids and rims on jars and place in a hot water bath for 5 minutes. Remove jars from hot water, label, and store in a dry place