// MAKES ABOUT 8 CUPS
This is the mother of ramen stock. It has a concentrated and deep flavor that is not for the faint of heart. It’s porky and fatty to the core, and it’s an insanely rewarding stock to make. I used to sit for hours waiting for that marrow cloud to rise up through the liquid. Even to this day, every single time I see it, I clench my fists above my head in victory. This famed cloudy pork bone stock is, again, simply bones and water, but the process to get what you want out of these bones takes patience.
In a large stockpot, place the bones and add water to cover. Bring to a boil over high heat and blanch the bones for 10 minutes. Drain the pot, let the bones cool, then run each bone under cold water, cleaning off the scum with your hands. Clean off as much dirt and impurities from the bones as you can.
Once cleaned, allow the bones to rest in the fridge for 2 to 3 hours to allow the marrow to come off the bone a bit and slide right out in the next phase of making our stock. (Meanwhile, wash your stockpot if using the stovetop method.)
3 pounds pork femurs, cut into 2-inch pieces (so you can look through the center of the bone and see the marrow)
2 pounds pork neck (or any other main scrap)
1 trotter
10 to 12 cups water (or 2:1 water-to-bones ratio using volume)
Two 12 x 12-inch pieces kombu
STOVETOP METHOD
Begin with a clean stockpot and your congealed bones. Add a 2:1 ratio of water to bones, or just enough water to cover (10 to 12 cups). You don’t want to drown them, but make sure they have enough room to roll in the moving pot. Affix your temperature gauge to the pot. Bring the stock to a boil (220°F) over high heat (it will take about 30 minutes). Once the stock reaches a rolling boil, reduce the heat to medium (190°F). If a filmy brown foam begins to rise to the top at this point, skim off as much as possible until there is no more.
Continue cooking at a medium boil for at least 6 hours (you can go as long as 8), then raise the heat to a hard boil. Slowly add water to keep the water level the same. Boil and agitate the bones until you see that marrow cloud and all the cartilage and soft tissue on the bones has literally melted into the stock. The bones should look like dinosaur bones when you pull them out, even with a slight chalkiness from the calcium leached from them.
While the broth is cooking, prepare a large glass or food-grade plastic bowl or container (Tupperware will melt; don’t use it here) to chill the broth in, and clear space in your refrigerator.
When the broth is complete, pull some of the largest and cleanest bones out to make room for your hand blender. Using a hand blender, carefully agitate the stock to release any extra bits of marrow and emulsify them into the liquid.
Strain your stock into the prepared bowl or container and then add the kombu. Allow it to steep in the broth for about 50 minutes at room temperature, then strain out and discard. Cover the broth and chill in the refrigerator until it is totally solid and gelatinous, a minimum of 3 to 4 hours or overnight.
When the broth is totally chilled and a thick layer of fat has formed on top, use a spoon to skim off the fat and reserve it for making Infused Pork Fat.
The tonkotsu will keep for 1 week in the refrigerator or 2 months in the freezer.
PRESSURE COOKER METHOD
Add the cleaned bones to the pressure cooker vessel, then add water using a 2:1 water-to-bones ratio (10 to 12 cups). Lock the top and set your cooker to high for 2 hours. Force the steam valve to release, which will bring the temperature of the stock up and force a boil.
When the top unlocks, unplug the cooker and allow the stock to rest for 1 hour, then return to a hard boil either on high in the cooker itself, or transfer it all to a stockpot and boil over high heat for 1 to 2 hours, or until the stock looks milky and cloudy. This means the marrow has come out of the bones.
At this point, inspect your stock. You’re looking for a few things: The stock should be opaque from the marrow of the bones, and there should be no soft tissue or cartilage left on the bones. The bones will appear chalky from decalcification. If the stock needs to cook longer, put it back on for another 30 minutes on high.
When the broth is complete, pull some of the largest and cleanest bones out to make room for your hand blender. Using a hand blender, carefully agitate the stock to release any extra bits of marrow and emulsify them into the liquid. For the last hour add the kombu and allow the essential glutamates to leach out and give your stock all the umami you are looking for.
Strain the stock into a large glass or food-grade plastic bowl or container (I do not recommend your typical plastic container; this stock will melt your Tupperware). Cover the broth and chill in the refrigerator until it is totally solid and gelatinous, a minimum of 3 to 4 hours or overnight.
When the broth is totally chilled and a thick layer of fat has formed on top, use a spoon to skim off the fat and reserve it for making Infused Pork Fat.
The tonkotsu will keep for 1 week in the refrigerator or 2 months in the freezer.
Pork Bones Note
Use organic and all-natural pork if possible. I bet your butcher at the market will be thrilled to sell you those bones. Ask them to cut your femur bones for you, too.
Stockpot Note
If using the stovetop method, use a large (8- to 12-quart) stockpot with a heavy bottom, if possible—the taller and skinnier it is, the better, as it limits the broth’s exposure to air and helps create a delicious fat seal on top.
Pro Tip
Once it’s finished cooking, it’s very important to cool a pork broth down quickly. I usually set up an ice bath in my sink for the stockpot or vessel and stir occasionally to continue the cooling process. If you live where the snow flies, use nature and cool your stockpot outside.