This is a great recipe to use up any excess plums from a productive tree. In order to keep the jam full of chunky pieces of plum, this recipe uses a two-stage method – the softened plums will absorb the sugar as they rest in the syrup and this will stop them rising to the top of the jar.
- 1kg/2lb 4oz plums, halved and stones removed
- 1 large lemon or 1 orange, juice only
- 700g/1lb 9oz granulated sugar
Put the plums, lemon juice and 150ml/5fl oz water in a heavy-based saucepan or preserving pan. Bring to a simmer and cook gently for about 5 minutes until the plums are beginning to soften a little. Add the sugar, a third at a time, stirring until dissolved, then remove the pan from the heat. Cover the pan and leave for a couple of hours or overnight so the mixture can cool – the plums will sink from the surface as they become heavier.
Return the pan to the heat, stirring to remove any sugar clumps on the base of the pan, and carefully bring the mixture to the boil. Increase the heat and bring to a rapid boil for approximately 10 minutes until the setting point is reached (see tips). Remove from the heat and leave to rest for 5 minutes to allow the fruit to settle.
Tip the jam into a wide-necked jug with a good pouring lip, then fill four sterilised jars to the brim. Seal immediately with the lids and store in a cool, dark place. The jam is best eaten within 1 year.