Dulce de Leche recipes

Having been quite taken by Dulce de leche ice cream and alfajores, I'm keen to make them myself. Dulce de leche is available here and here, and I'm quite certain I've also spotted it at Lidl, but apparently it's also easy to make yourself:
"Just put the can of condensed milk, unopened, in a saucepan with boiling water and simmer with the lid on for about 4 hours. Don't let the water boil dry though or the can is at risk of exploding!" (Emmario, UK Parents Lounge)

For further processing, the following recipes look rather good:
Scoopalicious Dulce de Leche and Chocolate Chunk
Cafe Johnsonia Dulce de Leche