In this recipe, I’ll show you how to make thịt ba rọi, or seasoned pork belly, for Vietnamese bánh mì. At sandwich shops you usually won’t find pork belly as an option. They’ll use other cuts simply to reduce costs. One difference between this recipe and xa xiu/char siu is the latter would call for pork shoulder and barbecuing. Since we’re going through the effort of making this at home we’re going to use fattier, tastier pork belly!
Choosing the pork belly
Something around 1.5 pounds produces a decent sized roll when sliced for sandwiches. If you choose something too big, you’ll need a bigger pot to cook it in, more water, and longer cook times. If your butcher only carries larger pork bellies you can always cut them down to size and cook more than one at a time.
Marinating the pork
Combine the onion powder, salt, soy sauce, and Chinese barbecue seasoning into a bowl, then distribute evenly over the pork belly and let it marinate for 1-3 hours or overnight. I actually let this marinade for 24 hours and it still tasted great without being over salted.
Tying up the pork belly
I made a quick video showing one way to tie the pork belly. There’s no need to get real fancy, you could just wind the twine around multiple times and tie it down too. See below: Roll and tie the pork belly in butchers twine and tie it so it holds together when you boil it. Don’t overtighten it because the string will cut into the skin as you cook it. This step is optional and mainly for looks when you slice the pork for sandwiches.
Cooking the pork
Next, add it to a pot of water with a quartered onion then boil it on medium to medium high to maintain a low boil. Rotate the belly 90 degrees every 15 minutes so it cooks evenly on all sides. Repeat until the skin is easily pierced with a chopstick, but not mushy and the belly should still be relatively firm. This should take about 90 minutes total depending on the size of belly and size of the pot. When done, remove from the pot, wait for it to cool, then slice thinly to add to your bánh mì sandwiches. Vietnamese baguettes are the way to go and the only place to get them is from Vietnamese bread/sandwich shops (or to make it yourself!). French baguettes and any kind of bread sold at American supermarket chains could work in a pinch, but it wont be quite the same. If you want a Filipino version of this entree, you can also fire up the grill and rotisserie to make Cebuchon–an equally tasty and crisp roasted lechon belly recipe.
