We made this delicious tonkotsu-style ramen soup with several pounds of pork soup bones from one of our pasture-raised heritage pigs. We mostly followed this recipe from honestcooking.com. (We don’t know the folks behind that website, but their recipe came up in a web search and looked good. It tasted good too!)
What follows are some notes from the process of making tonkotsu broth. This is a great way to use pork bones for a special occasion, like a New Year’s Eve dinner.
Crack and Boil the Bones
Tonkotsu is a pork bone broth. When we make it again we will just use pork bones. The recipe linked above calls for adding chicken bones, which we did, but the chicken bones didn’t add anything and could have been better used to make chicken stock. We used regular pork soup bones, not split pig trotters. Next time we will also crack the pork bones with a hammer or perhaps saw them in half to expose more of the marrow. If you do this make sure to wash the bones afterward to wash off any bits of bone dust.
We boiled the bones for 24 hours in our largest pot. There doesn’t seem to be any downside to cooking them this long. We did bring the bones to a boil first and then discard that liquid to get rid of any coagulated blood. This makes the broth look creamier and less brown. Honestly for us it was a waste of time as we would not have minded browner broth.
Along with the bones we boiled 2 large leeks halved and sliced, about 10 chopped up green onions, 1 large onion peeled and quartered, about 15 garlic cloves peeled and smashed, a half finger-length of ginger sliced (not peeled), about a cup of mushroom stems and sliced mushrooms, and 3 large pinches of salt.
If making this again in winter time (when else do you want your stove on for 24 hours?) we would leave out the green onions which don’t grow in our garden in this season and add an extra onion and more mushrooms, or perhaps some dried mushrooms which sometimes have more flavor.
Ramen noodles of course. Cooked. Not the instant kind. If you don’t have real ramen, use thin wheat noodles and boil them in water with a handful of baking soda. Ramen noodles are alkaline wheat noodles, so cooking wheat noodles in baking soda water (which is alkaline) mimics some of the effect.
Sliced chashu pork belly.
Boiled eggs (marinading these in leftover chashu sauce really does make them even better). Our eggs come from our free range layer hens.
Fried garlic slices (and the oil you fried it in)
Vinegar (we used a Chinese-style vinegar made from rice and wheat bran)
We added sliced green onions but while they make for a pretty dish, they really didn’t add anything outstanding to the flavor. It’s probably best to add things that bring out or compliment the flavor of the tonkotsu broth.
Chashu is Japanese braised pork belly. It is not cha shao (or “char siu”), which is a Chinese version of barbecue.
For our braising liquid we used garlic, ginger, onion, a few whole black peppercorns, several large spoonfuls of sugar, a splash of vinegar, 1/2 a cup of soy sauce, and 2 parts apple juice to 1 part water (how much braising liquid you need depends on how big your pork belly is.)
Get some pork belly
Pork belly is the same cut that bacon is made from. We encourage people who buy half hogs from us to get uncured pork belly and buy bacon from us separately. Yes, the bacon is a bit more expensive this way, but you know exactly how much bacon you are getting. (The size of a pig’s belly varies, of course, so some pigs make more bacon than others.) We would love to sell pork belly on its own, but because bacon is so popular we would have to put quite a high price on the pork belly to justify not making bacon out of it.
Roll it up
The goal is to cook this low and slow so that it braises and stays juicy and delicious. We set the oven to 250 degrees Fahrenheit but a pork belly is a relatively thin slab which will still cook quickly and dry out. If you roll it up tight and tie it with kitchen twine, this decreases the surface:mass ratio, which helps the pork belly retain moisture while cooking longer. It needs around 5 hours to cook properly but the longer it goes the better it is going to taste.
It might be even better the next day
Boil the braising liquid before using it so that the sugar dissolves and the flavors mix together. Braise the pork belly in a sturdy pot in the oven and turn it every hour so that all sides of the roll get to cook in the braising liquid. When it is finished slice off rounds. This is normally a main addition to tonkotsu ramen (made with pork bone broth). However…if you keep it in the braising liquid after cooking marinate the cooked chashu pork belly overnight in the refrigerator, you may find that it is even better the next day. It’s especially good if you pan-fry slices over high heat, as if cooking bacon, as the edges will get brown and crispy but the middle will remain soft and juicy.