Method

1. Line a 33x23cm/13x9in Swiss roll tin with baking parchment. Preheat the oven to 50C/120F/Gas ¼.

2. Place the chopped plums in a pan with 200ml/7fl oz cold water, cover with a lid and place over a medium heat. Bring to a simmer and cook, covered, for 15 minutes, or until the fruit is very soft.

3. Remove the lid and mash the fruit using a potato masher. Stir in the sugar and a squeeze of lemon juice.

4. Place the pan back on the heat and cook, stirring continuously for another 10 minutes, or until the mixture has thickened.

5. Purée the fruit using a stick blender or food processor, taking care to ensure the mixture is completely smooth.

6. Carefully spoon the purée into the prepared tray and level the surface. Bake for at least 10 hours, or until completely set with a leathery texture.

7. Allow to cool then carefully lift away from the baking parchment. Run a pizza cutter down the length of the leather to cut into 3cm/1in strips then roll up tightly. Serve immediately or store in an airtight container.