Soak the short ribs them (yes, soak them—it drains the ribs of excess blood) in a very large bowl of cold water for two hours, changing the water after the first hour.
Drain the ribs and put them in a large pot or Dutch oven, cover with water, and bring to a boil.
Boil ribs for five minutes, skimming off any residue, then drain and rinse in cold water.
If you want to feel smart, wash the pot you just used to boil the ribs; you'll braise the meat in it soon.
In a food processor, pulse onion, kiwi, and pear until puréed.
Scrape the mixture into a bowl and stir in mirin.
Place the clean short ribs in the pot you just washed and spoon the onion/kiwi/pear mixture over the meat.
Cook over low heat for 15 to 30 minutes.
In a medium bowl, combine soy sauce, garlic, and brown sugar.
Add the soy sauce mixture and water to the pot, give everything a good stir, then cover and bring to a boil.
Turn the heat down to low and simmer for 30 to 45 minutes.
Add the chopped carrots and daikon, stir and cover again, and cook for another 30 minutes until vegetables and meat are cooked through and you can easily pierce through them with a fork.
Serve with steamed rice and kimchi—I love a crunchy daikon kimchi. Like any good braise, this one only gets better with time.