The name sounds very fancy right but its such a an easy thing to make, the only place you will loose the money is your gas bill as it has to be cooked for at least 2 1/2 hours . So when you make it always make a few extra cans , so you will always have some ready in your kitchen when ever you need it.
A few key things you have to remember when making this is :
1. Always make sure the water level in pot is above the can if it goes below it is said that the can might explode.
2. Always cook at a medium high heat, a constant boil not gentle simmer .
3. Once cooked , Cool the can completely , as it will erupt like a volcano if you tried to open a recently cooked can of condensed milk which is still hot! So its best to make this a day ahead.
So here is how to make it:
Place the can of condensed milk ( or few extra cans) in a saucepan and fill it with water ( tap water would be fine) till the water level is well above the can.
Place the pan over a medium heat and bring to boil and then boil over a medium high heat for at least 2 1/2 hours, or 3 hours. Check the pan now and then to make sure that the water level remains the same, that is above the can. Top up with more water if the water level starts to decrease.
After 3 hours, I think 2 1/2 gives a lighter caramel so I would suggest 3 hours rather than 2 1/2 , switch off, remove the can and leave to cool ( this can take a few hours at least), so best you make these ahead and there is always a delicious can of dulce deleche when ever a recipe calls for it.
Once cooled ,Use as need. You can store them in the cupboard till you need them.