Yellow plum jam
2 kg of yellow plums
600 g sugar
50 ml cognac
½ tonka bean (optional)
Juice of ½ lemon
Wash and halve the plums. Remove the pits. Place the fruit in a large saucepan. Pour over the sugar and let stand 1-2 hours to let the juice come out.
Bring to a boil and cook until the syrup thickens. Meanwhile, flavor with cognac and grated tonka bean. Check with a drop on a cold plate whether the jam is ready. If it tends to freeze and not follow the inclination of the plate, the jam is ready. Add the lemon juice. Heat for another 1-2 minutes.
Pour the yellow plum jam in warm clean jars. As the jam is still hot, seal the jars tightly with their lids (soaked in boiling water). Cool the jars upside down on their lids. The curved part of the lids must be sucked in and not move when the jars cool completely.