I didn't find it last time, so I did it at home. It is super easy. All you need is just of sweetened condensed milk (1 can). Instructions
Preheat the oven to 425 degrees F.
Place the sweetened condensed milk in a pie plate or similar baking dish, and cover it tightly with foil.
Place the covered dish in a larger pan, and pour hot water into the larger pan until it comes about 1 inch up the sides.
Bake in the oven for about 2 hours (checking every so often to refill with water if needed), or until the desired color and thickness* are achieved.
Whisk the dulce de leche to smooth out any lumps.
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