Chashu is a critical topping for many types of ramen and is often times the hardest thing to get right. When it’s done well, the sweet savory skin will melt in your mouth, adding a punch of flavor to the noodles. The fat will give the broth even more richness and the succulent meat will fall apart with the slightest bite. The chashu will accent and enhance a good bowl of ramen and make it great.
My husband and I like to visit some great ramen shops whenever we travel to other cities to taste different kinds of ramen. We often make shoyu ramen and miso ramen at home so the whole family can enjoy it whenever we want.
Traditional ramen shops often top their ramen with 2-3 pieces of chashu. Unlike Chinese chashu or “char siu” (barbecued pork), the Japanese chashu uses pork belly that is rolled into a long cylinder and slow cooked in a pork/chicken broth, then transferred to a soy-based broth that consists of soy sauce, sake, and mirin and cooked for hours, as you can see the pictures below. If you want to make the chashu like this, you have to ask your butcher for a special cut. But I was able to just buy the pre-cut ones (much smaller) from the Asian grocery stores and make it at home.
After researching many Japanese chashu recipes and a few attempts at home, I am finally happy with the texture and flavor of my Instant Pot version and can’t wait to share the recipe with you!
Why Rolled Pork Belly vs. Slab?
Most home recipes and even some ramen restaurants use the slabs for the sake of saving time and labor. Serious Eats has a really good article explaining the differences between these two shapes. Simply put, the rolled pork belly is moister and juicier than the slab ones.
Time and temperature are the most important…but surface area-to-volume ratio also plays a role. The more exposed surface a piece of meat has, the faster it cooks, and the more easily it loses moisture. And of course, the more moisture it loses, the dryer it becomes.
The end goal of simmering pork belly using lower heat is to get a melt-in-your-mouth texture. The higher cooking temperature it cooks, the drier meat it becomes. This is what you have to consider when making chashu in an electric pressure cooker. The peak working temperature of Instant Pot is 239°F-244°F (115°C-118°C). If you look at the chart below, cooking the slab pork belly in the pressure cooker could squeeze out much more moisture than regular slow-cooking method even though the Instant Pot doesn’t always maintain the peak temperature.
After the rolled pork belly is cooked, the lean part outside that has direct contact with the broth is noticeably drier than the part inside. But that’s ok because most of the meat inside is insulated with the skin outside so that it is evenly and gently heated. So tying the pork belly firmly is the key to tenderness and keeping a nice shape for final presentation.
Blanching the pork
This is a very common technique in Asian cooking to get rid of excess fat, gaminess, and impurities to get a cleaner taste of the soy-based sauce. If you plan to use the sauce for making other dishes or chashu anther time, it’s worth doing this step.
IMPORTANT NOTE: I mentioned that you can use Instant Pot for searing, but it was a HUGE MISTAKE! The skin is very tender and has sugar from the soy broth. It’ll stick to the pot.
Roll up the pork belly with the skin side out. Run some butcher twine under the middle of the pork. If your pork belly is long and wide, start under the far end instead of the middle. Tie a double knot to secure the pork tightly. Leave the short end about 2 inches long. Pull the long end to wrap around the pork belly and tie another double knot.
In a pot of boiling water, blanch the pork belly for about 10 minutes. Transfer the pork to a pressure cooker. Add soy sauce, leek, ginger, water, sake, garlic, and mirin.
Cover with the lid and cook for 90 minutes on high pressure. Do a slow release and, after 20 minutes, open the lid.
Note: If the pork is not submerged in the sauce, cook for 40 minutes and flip it over and cook for another 40 minutes.
Heat a skillet over medium-high heat and sear all sides of the pork until it's golden brown. DO NOT use Instant Pot for searing because the skin would stick to the pan and get riped off.
Once the pork is cooled down, transfer the meat and sauce to a large sealed container or a zip-top bag. Put it in the refrigerator overnight or until it's completely cool. This way the pork is easier to slice thinly after cooling, and this also gives the pork more flavor.
When it's ready to serve, skim off the fatty oil on the surface. Transfer the pork to a cutting board and strain the sauce. Reserve the sauce for marinating soft-boiled eggs or for making more pork belly.
Take out the butcher twine. Cut the meat thinly using a very sharp knife. Reheat the slices in soup broth or heat it in a saucepan with the sauce until hot.
- If rolling up the pork is too much work, you can cook the slab for 1 hour in a pressure cooker, but there'll be a difference in texture.
- Freeze the marinated soy sauce for another use if needed.
- I don't recommend using pork belly without skin.