I know this dish came from China. My grandparents, parents, aunts and uncles all know how to make them. They just don't know what this is called. After I moved to Los Angeles, I discovered a Japanese dish that is quite similar to it, but slightly sweeter. The flavor of it is quite nostalgic and I do prefer to sweeter taste of this thing. I think this is by far the most complicated thing I have ever attempted, because most of the things I've done are all mix up the ingredients and throw it in the oven/pot/etc.

So here are the ingredients:

1. 1 Lb of pork belly - I used short ribs because I am in SF now, and the mean Cantonese people didn't want to listen to my explanation or attempt to understand what I was saying in Mandarin...
2. 1 Potato
3. 4 table spoon of soy sauce
4. 2 table spoon of mirin
5. 4 table spoon of sake
6. 4 table spoon of sugar
7. A little bit of ginger, no bigger than 2cm^3
8. 1 stalk of scallion

And the instruction:

1. Fry the pork in a pan until it's browned on all sides (so it doesn't fall apart)
2. Cut it in large cubes (I cut the 1.3lb piece into 2 large pieces) and place it in the pot, cover it with water (literally, the water needs to be higher than pork)
3. Boil in water, add sliced ginger and the stalk of scallion, then turn it down to medium heat to simmer for 90 minutes
   
4. To be sure it's done, stick a skewer/chopstick through it to see if it could easily be poked through
5. Remove the meat from the pot, place it on the plate until it's cooled, and pick off the fat
6. While the meat is cooling, let the soup cool and skim off the fat as well. I put it inside the fridge to make the cooling process faster. The fat will solidify and become easier to pick off
7. Mix the mirin, sake, and sugar
8. Add the solution to the now skimmed soup, and put the meat in it
9. Bring it to boil, then turn it down to medium heat and simmer for 70 minutes - becareful not to let the soup dry up, it will caramelize...then it turns into an entirely new dish XD
   
10. In the mean time, add the soy sauce gradually (2 or 3 times)
11. Now boil the potato for 10 minutes, and consult waitless.org for fast peeling action XD
12. Cut the potato into 6 cubes and add it in for another 20 minutes of simmering, then serve! (add water if necessary, because potatoes soak up the soup)