Have you ever heard of this?

My stepmother Lois, who is something of a domestic goddess, had a can immersed in a small pot of simmering water on her stove. I was somewhat skeptical when she told me she was making caramel topping just by heating an unopened can of sweetened condensed milk.

Sure enough, when she opened the can, the s.c.m. had browned to a caramel color and tasted pretty much like the real thing. The only catch is that with the cost of energy, it might actually be cheaper to buy a container of caramel topping as opposed to warming this on the stove for 4 hours.

UPDATE:

An old recipe for dulce de leche that some people still use calls for placing an unopened can of sweetened, condensed milk in a pan of water and simmering until the milk turns to caramel. This method is unsafe, though, because the can could explode.

A more painstaking but safer method is to transfer the milk from the can to the top of a double boiler and cook over simmering water for about two hours, stirring every five minutes. Carry around a cooking timer to remind you when to return to the kitchen and stir.