How to prepare a delicious dulce de leche
Melt the butter in a high-sided non-stick pan.
Add the sugar, vanilla sugar and a pinch of salt and allow to caramelise briefly. Add the cream and the milk and stir to dissolve the caramel.
Simmer on a moderate heat for around 45 minutes until it forms a thick cream, stirring at least every 5 minutes.
The dulce de leche is ready when it drips slowly from the spoon.
Spoon the cream into a jar rinsed well with hot water, seal firmly and leave to cool.
Store in the fridge until needed.