“Mix together whole milk, whipping cream, and sugar in an empty 1 pound coffee can. Close the lid and shake vigorously. Place the coffee can containing the ingredients into a larger coffee can. Pack the empty space with ice cubes and rock salt, close lid, and roll the two coffee cans for ten minutes. Add toppings, roll for another ten minutes, and open the lids to both coffee cans.”

via The Secret Yumiverse