5.

Once the lid is on, check the pot after 15 minutes. It should be at a slow rolling boil. If not, increase or decrease heat slightly to adjust boiling speed. Boil broth until pork fatback is completely tender, about 4 hours. Carefully remove pork fat with a slotted spatula. Transfer fatback to a sealed container and refrigerate until step 7. Return lid to pot and continue cooking until broth is opaque with the texture of light cream, about 6 to 8 hours longer, topping up as necessary to keep bones submerged at all times. If you must leave the pot unattended for an extended period of time, top up the pot and reduce the heat to the lowest setting while you are gone. Return to a boil when you come back and continue cooking, topping up with more water as necessary.