Pour the sour milk into a clean dishcloth and drip off the thin liquid. Let the sour milk drain for a couple of hours until you get a lightly fluid consistence with about 1.3-1.5 l remaining.
If you want a thicker consistence (like cream cheese), drain the sour milk for about 4 hours.
Eat the drained sour milk with plum compote and toasted oatmeal for breakfast.
Toast the oatmeal flakes in a frying pan until crisp and golden.
Add honey, butter and salt to the pan and stir well with a wooden spoon until the oatmeal is caramelized.
Pour the toasted oatmeal flakes into a tray and let them cool.
Rinse the plums well and pour them into a pot with sugar and the water clinging to them.
Boil the plums, until they soften and the pits start appearing.
Filter the compote in a course sieve when it is fully cooked, so the pits remain in the sieve. If the compote is too thin, boil it in a pot, stirring constantly, until it reaches the right consistency.
You actually want 4 dl double cream. Where unavailable pour 8 dl whipping cream into a container and refrigerate for at least 8 hours. Skim off the top half and you have 4 dl double cream.
Whip the double cream until lightly foamy and fold in the cooled plum compote and serve in glasses with cream puffs.
You can garnish on top with some small fresh plums.