This is a very South and Central American way of making caramel, but I have a friend who learned how to do this while on a mission tour in Russia. I think that folks everywhere have been doing this since sweetened condensed milk was invented, because my Cajun friends say their grandparents did this back in the day as well. The caramel that results from this miraculous metamorphosis is something like dulce de leche (but not quite). You get a creamy, coffee colored caramel that's super sweet with a milky flavor behind it all. It's perfect for dipping fruit, on top of ice cream and dessert breads, and for making a ton of fabulous desserts like banoffee pie. Mr. OFM likes to eat this with a spoon and thinks I am amazing. If any of you heifers tell him how easy it is to do this, I will cut you.
How to make luscious caramel without killing yourself and/or destroying your kitchen
The Eagle Brand website will tell you NOT to make caramel in the can. This is highly dangerous because the can will explode if you don't mind your water. (I don't doubt it will!) I think the Eagle Brand folks are just afeared of a litigation, y'all. The magic is that you take sweetened condensed milk and you turn it into caramel while it's still in the can. Duh, Eagle Brand. If I had you at highly dangerous, then keep reading.
Once I figured out I could turn sweetened condensed milk into this viscous gold in my slow cooker, I felt like a mother flippin' genius. No fuss, no muss, and no highly dangerous cooking scenarios either.
So you don't make rust rings in the crock, line it with foil. Peel off the labels from the cans of sweetened condensed milk and place the cans in the crock. Cover with water- enough to completely cover the cans plus an extra inch or two. Set on low and let cook for 6 to 8 hours.
Be sure to check the crock every now and then to make sure the water level is good. It should be because it's covered. You just want to avoid explosions. Right? Right. Now, in all honesty, I've fallen asleep and left this sucker going overnight before. Alas, no explosions. Not even an irate gurgle or two.
Remove cans from crock using tongs (they will be hot- duh) and allow to cool completely. You'll get a can shaped mass of caramel once you plop the contents into a bowl. You can slice it or just eat it with a spoon.
I usually only use one can at a time, so I mark the other cans with the date and their contents (example- 12.15.11 caramel goodness) and place them in the pantry. I've never gone longer than 6 months with storage, so I don't know exactly how long they keep. At least 6 months for sure. I like to make some ahead of time because it's nice to have caramel on hand for dipping fruit and as a topping for ice cream.