Place all ingredients in a pan, stirring gently to combine.
Bring the mixture to a boil over medium-high heat, then reduce heat to low and simmer for 10-12 minutes until the plums are soft and liquid is syrupy.
Remove the plum skins which separate easily from the plums when they are cooked.
Allow the skins to cool enough to handle and then chop them up a bit and return them to the compote.
Set the compote aside to cool.
Notes
If you have the time, the compote is best made a day ahead of time to allow the plums to steep in the syrup. It can be kept in the fridge for up to one week.