Place all the compote ingredients in a small saucepan over a medium heat. Simmer gently for 10–12 minutes or until softened and slightly sticky. Leave to cool. (The compote can be prepared in advance and chilled.)
Put the milk, measurement water, vanilla extract, cinnamon and salt in a large saucepan over a medium heat and bring slowly to the boil. Stir in the oats, then reduce the heat and simmer gently, stirring occasionally, for 8–10 minutes until creamy and tender.
Spoon the porridge into bowls, scatter with the almonds and serve with the prune compote.