Dulce de leche is a sort of milk jam, loved by the young and adored by everyone else in Argentina.
It is often eaten by itself by the spoonful, or spread onto meringues, macaroons, flans or on top of ice cream.
It is the traditional filling between two alfajores which are traditional biscuits made of almond paste.
It is very easy to make to make a substitute at home — take a can of condensed milk, put it in a pot of water, without opening it, and bring it to the boil.
Keep it simmering on a high heat for an hour or so, turning the can from time to time.
Take the can out of the water and leave it to cool down without opening it. When completely cold the dulce de leche is ready. It is not very orthodox but is never the less quite delicious!
If you cannot visit Buenos Aires to buy the local version, a company called Merchant Gourmet in the UK sells it