Technically speaking, everything is, but here's the rub. If you don't do this right, the can could explode scattering 210F molten Caramel and water all over your kitchen and you if you let the water boil down.
To do this safely, always, ALWAYS, always make certain the can of Sweetened Condensed Milk is on its side and fully submerged in water. Ideally you should have an inch or two covering the can.
I used a spaghetti pot to give me extra room. I had absolutely no problems with this recipe. It is one of the simplest I could find.
Ok dire warnings aside, it truly is a trivial recipe to make a caramel sauce. The result was tasty, sweet and had a bit of a "Sweetened Condensed Milk" taste to it, so you should do a test batch and see if it works. This will be best for "bold" items like Chocolate Cakes, Cookies and anything else with a strong flavor.
The recipe is simple:
1 Can Sweetened Condensed Milk. Use your favorite brand, you may double or triple the recipe easily.
1 large pot of lightly boiling water.
You don't want a "rolling boil". A light bubbling is fine. I tested the temperature of my water with an Instant Read Thermometer for giggles, and it was at 210F, 99C for the entire time.
- Submerge COMPLETELY your can of Sweetened Condensed Milk in the boiling water.
- The Can MUST be placed on its side.
- The Can MUST be submerged, ideally by an inch or three of water.
- DO NOT ALLOW THE WATER TO BOIL DOWN BELOW THE TOP OF THE CAN.
- Boil the water for 2 hours and check it periodically to make sure it hasn't boiled down too far.
- The resulting Caramel will have the consistency of a hard boiled egg at room temperature.
- Do Not Open the Can until it has cooled sufficiently. Around 1 hour or more may be needed since it will be under pressure until it reaches room temperature.
- Do Not Open the Can until you can handle it safely without burning yourself.
If you do allow the water to run below the top of the can, Kittens may die, flowers will fail to bloom, your paint may peel from the wall, and you are not a very nice person.
The reasoning is that if the can breeches the top of the boiling water, there will be hot and cold spots and the can may burst. If it bursts it will be ugly.
Why do this? Well if you have an Abuelita handy she will tell you that in Latin America, everyone makes caramel this way. They just check the water every 15 or so minutes to make sure that the cans are covered. She will also tell you that I may be overreacting about the "Explosive" part.
As you can see in the picture, I did it. The Republic did not fall (yet). The kitchen is still it's usual warm cream color, and that isn't due to sweet caramel goodness painted on my wall like a Jackson Pollock painting.
I bloody hate his "art". My dog could do better. Oh wait, did I say that in my Outside Voice?