I have talked about konnyaku  before, the almost zero calorie, rubbery-jellylike food that makes me really wonder at the ingenuity of people of the past. Why would they think that an almost flavorless, almost nutrient free substance would be edible?
Well, konnyaku is not about its innate flavor - it’s all about texture. And since it really has so little calories, it’s a great addition to meals for the dieter, giving a feeling of fullness.
I tend to make konnyaku dishes when I want to really watch the calories, but still have a hearty appetite.
Tosa (土佐）is the name of the region that is currently Kouchi prefecture, known for katsuo or bonito fishing, hench the name.
Drain and rinse the konnyaku. If you have a thick block (about 5cm/ 2 inches thick) cut in half lengthwise, then cut into thin strips.
This is optional, but if you cut the strips into tanzaku they are quite pretty. Take a look at this diagram:
Make a cut in the middle of each slice, leaving a little bit uncut at both ends. Then, turn one end into the cut slit.
They turn into little twisted rope-like shapes, like these.
(Alternatively you can just cut the konnyaku into cubes or strips, or even tear the konnyaku into chunks with your hands and a spoon. For this bento  I used cubed konnyaku no tosani.)
Boil the cut konnyaku shapes in plenty of water for about 5 minutes, then drain well.
Put the rest of the ingredients except for the bonito flakes in a pan and bring to a boil. Put the konnyaku in, and simmer over medium heat, stirring occasionally, until the liquid is almost all gone.
Add about half the bonito flakes and mix well - the bonito flakes should absorbe any remaining liquid. Top up with the rest of the bonito flakes and mix again. Serve warm or at room temperature.
The world kinpira indicates that it’s a spicy stir-fried dish with chili and sesame. (See carrot kinpira  on Just Bento.) I’ve combined konnyaku with thick fried tofu (atsuage) here, but you could make it with just konnyaku too.
Cut the konnyaku into thin strips. Boil in plenty of water for about 5 minutes, and drain well.
Cut the atsuage into thin strips.
Put 1/2 of the sesame oil into a large frying pan. Put in the atsuage strips, and gently fry until brown and firm. Take out the atsuage.
Put the rest of the sesame oil into the pan and add the konnyaku. Stir-fry until the konnyaku strips get a bit lighter in color all over. Add the atsuage strips back in the pan, and add the soy sauce, mirin and sugar, and toss around well to coat everything. Add the chili pepper and sesame seeds and toss toss toss.
Either dish makes a nice space-filler in a bento box, and will last for a few days (well covered) in the refrigerator.
Just one caveat about konnyaku: be sure to chew it well before swallowing. You will likely not choke on konnyaku strips, as the shape does not lend itself to clogging up your esophagus like fruit-flavored konnayku jellies can. But if you don’t chew, the pieces will just travel down your gut..more or less whole. Which, in some people, may cause some distress. The same goes for the popular shirataki noodles by the way.