Rinse and drain 2 pounds fresh plums. Halve them and remove the pits. Then cut each half in half again, resulting in quartered plums.
Place the plum quarters in a large, wide saucepan. Add about a quarter of a cup of water, just enough to moisten them.
Turn the stove to medium-high heat and cover the saucepan with a lid. Soon, the plums will begin to cook. The added water will help the fresh fruit release its juices and prevent them from burning.
Reduce the heat to low, remove the lid, and let the plums simmer until they form a thick, chunky sauce. This process will take about 20 minutes. Stir occasionally with a long-handled wooden spoon to ensure even cooking.
Once the plums are soft and swimming in their juices, add 1 cup granulated sugar and stir well to combine.
Continue cooking for another 20 minutes. The liquid will evaporate, and the klevela will thicken slightly, while the fruit pieces will still remain visible.
Stir 2 Tablespoons spiced rum into the plum compote.
Prepare jars with screw caps by washing them thoroughly in the dishwasher or by hand with hot, soapy water. Rinse the jars well and set them aside to dry completely.
Using a ladle, carefully pour the hot plum mixture into the clean, still warm jars. Wipe the rim of each jar to ensure it is clean, then place the lid on top and tighten it. Turn the jars upside down and leave them to cool completely.