In advance: Use a cup with a volume of 200-250 ml as a measure.
Cover all ingredients with water and bring to the boil in a pressure cooker. Close the lid and cook for 10 minutes. Switch off the pressure cooker and let stand until completely cooled down.
Add more water as required and bring to the boil again. Transfer to a thermal pot and leave to stand overnight. In the morning the porridge is still lukewarm.
The porridge can be served with yogurt and fruit compote, nuts, etc. Any leftover porridge can be warmed up and eaten the next day.
Kruska can also be prepared in a normal saucepan, it will then take longer.