Plum, Apple & Cinnamon Jam

It's now plum season & we are picking 2.5kilo's a day, every day,  from our tree's & its difficult to keep up with preserving them. I have been making lots of plum jam but as they keep coming I decided to try something different. This is a really lovely preserve with a nice aroma as well as being very tasty.

750g sml Plums
750g Eating Apples peeled, cored & chopped
1tsp Cinnamon or more to taste
450 ml Water
1.5 kg Sugar
Put whole plums & chopped apples in a large pan with the water. Heat till plums go soft & release their stones easily, when pressed against the side of the pan. Use a skimmer to take out the stones. Add sugar ^& stir to dissolve. Bring to a rapid boil stirring frequently to stop jam from catching. Boil like this until the jam has reached setting point. Check this by putting a plate in the freezer & putting a tsp of jam on it, leave for a min & if the jam wrinkles then setting point is reached. Jam won't be fully set until it has cooled right down.
Have 3 x 1lb jars already sterilised & fill.  Secure lids & as it cools down the lids should pop.