Boil the fuki stalks in heavily salted water to remove bitterness,
discard the water.
If your fuki is harvested later in the season, it will be more
bitter and you should do this twice.
The online recipe says peel, but I don't think
you need to do this at this stage, as the outer skin tends to come
off in the next step.
Let soak overnight in fresh water to continue the process.
Snap the stalks by hand, and devein with each snap.
You want to remove as many of the veins as possible, as they're
much tougher than celery veins and not easy to eat.
Stop when you get down to 3-4 cm lengths.
Cover the abura-age in water, bring to a boil, then discard the
water to remove excess oil left over from the manufacturing process.
Slice the abura-age into ribbons about the same size as the fuki.
At this point, you can finish the recipe the easy way (that I found
online) or the correct way (that my mom helpfully provided).
The easy way is to place all the ingredients in a medium
saucepan at this point,
bring them to a boil and then simmer until the fuki softens.
The problem with the easy way is that the abura-age will end up
being under-seasoned and the fuki over-seasoned.
So my mom says to forget the dashi ingredients listed above,
eyeball a concentrated dashi with water, kombu powder, katsuobushi
(bonito flakes), powdered ginger and mirin or sake. I know
she would add other secret ingredients too depending on her
mood and what was at hand. Simmer the sliced abura-age in your
concentrated dashi until it has a good combination of salty,
sweet, tangy and umami flavours. Reserve the abura-age, dilute
the dashi to approximately what the original recipe called for
by adding water (I'd guess a factor of three or so). Add the
fuki. Simmer until it begins to soften, add sugar or other
sweetener (honey, maple syrup, brown sugar) to taste. Add shoyu
just before removing from heat. For kansai-style, use a richer
dashi and salt rather than shoyu, which results in greener
(rather than browner) fuki.
The original recipe says this serves four. Not sure how, as it's
not something you eat a lot of at a time. I'd serve it as a side
dish with rice and fish, as I would any other Japanese vegetable
dish. Keeps for a few days in the fridge, reheats well.