Boil a pot of water and put any bony parts of 400 grams buri in a bowl (leaving any meaty parts for the end). Pour the hot water over the fish until the surface layer becomes opaque (about 10 seconds)
Drain the fish and rinse with cold water. Use a small spoon to scrape out any dark areas with clotted blood.
Add the cleaned buri to a pot along with 4 cups dashi and bring to a boil. If you did a good job cleaning it, there shouldn’t be any scum that floats to the surface, but if you see any impurities float to the surface, skim them off.
Add 145 grams daikon, 85 grams shiitake mushrooms, 85 grams burdock root, 85 grams carrots, and 15 grams ginger and simmer until tender (about 15-20 minutes).
Add 3 tablespoons miso to a ladle and dissolve by adding soup and stirring. Both dashi and miso vary wildly in salt, so taste the soup and add more miso if needed. I ended up adding another tablespoon of miso.
Add any meaty parts of the buri and 2 scallions and simmer until the fish is cooked, but do not let it boil.