Wash the soft plums thoroughly, peel them, hold them tightly with your hands, crush them, only remove the pulp and remove the seeds. Cut the hard parts roughly with a knife. Boil the whole thing without peeling it, and then remove the skin and seeds through a sieve, but it was easier for the plum to step back and do this, so I did this.

Combine the sugar with the plum pulp and put it over high heat first. I didn't have enough white sugar, so I used all the sugar in my house, so I also used organic brown sugar. It doesn't mean much, so you can use the sugar you have at home. When it boils, bubbles form and start to boil. Reduce the heat to medium and roll the foam from time to time. When you boil it with a mixture of plums and sugar, water forms on its own. And when the amount boils down to about two-thirds of the first time, reduce the heat to low and stir occasionally so that it doesn't get pressed. This is the worst part of making jam. But if you don't stir, the bottom will burn, so make sure to stir.

Bring to a boil over low heat, stirring constantly, until the amount is reduced to 1/2 at the beginning. Be careful because if the fire is too high, the jam can suddenly splash.

Finally, if you put a ballad on the bread, the delicious sweet and sour plum jam is completed. I have a lot of plums, so I boiled it for about 2 hours in total. But if the amount is small, it doesn't take this much time, so don't worry too much. If you want to keep the jam in a bottle for a long time, turn the bottle upside down in boiling water and disinfect it. When the water dries up, put the hot jam and close the lid. Then, put the bottle upside down and store it in the refrigerator.