I had this years ago and have never come across it again. I totally miss it, hence I'm trying my luck to replicate it. This is my second attempt on this dish. It's definitely much better my first attempt. ;)
If you would like try it out, here's how I did it. I soaked about 4 to 5 tablespoon of glutinous rice, which is enough for 2 squids, in water BUT seasoned with a tablespoon of light soy sauce, 1/4 tablespoon each of sugar and mirin. I soaked the rice for 3 hours.
Meanwhile, remove the innards of the squids. When the rice is done soaking, stuff the rice in the squid till 3/4 full. Use a toothpick or skewer to seal the opening. However, be careful not to tear the squid because it will be harder to secure it again and not having it 'explode' while cooking.
Place the stuffed squids in a pot with enough water covering it. Add in 2 tablespoon of light soy sauce, 1 tablespoon Mirin, and a 1 tablespoon of sugar. Bring it to a gentle boil then reduce to a simmer. Continue simmering for 3 hours. Turn the squids around in between cooking. It's alright if the sauce reduced to 2/3. However if it get to thick, add hot water to dilute it.
I used a thermal pot on my second attempt on this dish and I didn't have to add water. I just had to reboil it once. However, directly cooking does make the squids more tasty.
Remove the squids when it's done and let it cool a bit before you slice it. It's a little tricky slicing it. You might want to oil your blade to do it. Meanwhile, turn up the heat and boil the sauce to thicken it a little.
Drizzle some thicken sauce over the sliced squid and serve.
{ This is how it looks for my first attempt on the stuffed Squid; simmering for 3 hours over direct heat, ie, not using the thermal pot. The glutinous rice was plain and bland as I did not season it but the squid was in a deep shade of brownish orange. You can see from the rings that sauce had penetrated into the squid. }
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