Instructions

1. 1

   Sterilise four screw-top jars of 250 ml each and their matching lids in a large pan of vigorously boiling water, then lift them out with tongs and leave them to drain on a clean cloth. Only germ-free jars keep the jam for a long time.

2. 2

   Wash the pumpkin, halve it and scrape out the seeds and fibres with a spoon. The skin of the Hokkaido stays on, as it softens while cooking and gives colour.

3. 3

   Taste a small raw piece: if it tastes bitter, the whole pumpkin is thrown away, because the bitter compound cucurbitacin cannot be cooked out and causes severe stomach and bowel problems.

4. 4

   Cut the pumpkin into small cubes and weigh out about 1 kg.

5. 5

   Wash the oranges in hot water, grate the zest finely and squeeze out the juice. Squeeze the lemon, peel the ginger and grate it finely.

6. 6

   Cook the pumpkin cubes with the orange juice, the lemon juice, the ginger and the cinnamon stick covered over medium heat until soft.

7. 7

   Take out the cinnamon stick and purée the mixture finely with a stick blender.

8. 8

   Stir in the preserving sugar 2:1 and the grated orange zest, bring everything to the boil while stirring and then let it boil hard over full heat, stirring constantly.

9. 9

   For the set test, put a blob on a cold plate; if it firms up after a minute, the jam is ready. If it stays runny, boil it for another minute and repeat the test.

10. 10

    Pour the boiling hot jam into the prepared jars at once, to about 1 cm below the rim, wipe the rim with a clean cloth and screw the lids on tightly straight away.

11. 11

    The jars do not have to be turned upside down; simply leave them standing until they have cooled completely. As they cool, the lid pulls audibly inwards.