Preheat the oven to 400°F (200° C).

Pour the sweet condensed milk into a shallow baking dish or a glass dish and cover with aluminum foil.

Place this dish inside another larger baking dish and add hot water until it reaches halfway up the side of the condensed milk dish.

Let it bake for around 2 1/2 hours.

Check once in a while because maybe you will have to add more water.

When it's browned and caramelized, remove from the oven and let cool.

Once cool, whisk until smooth.