Cut your beef short ribs into their individual bones and remove any excess fat on top.
3½ lbs bone in short ribs
Season beef short ribs lightly with salt. Be very careful because miso paste and soy sauce are both very salty already.
1 tbsp salt, 3½ lbs bone in short ribs
Coat the short ribs in flour.
2½ tbsp flour
Sear the short ribs on each side in a hot pot with some oil. Should take 3 minutes on each side then remove from the pot.
Quarter your two onions and add them to the pot along with the garlic cloves. Stir for 1 minute.
2 yellow onions, 7 cloves garlic
Add miso paste, soy sauce, and mirin, stir for 1 minute.
¼ cup miso paste, ¼ cup soy sauce, ⅓ cup mirin
Add the seared beef back into the pot and top it off with beef stock. I used about 1½ liters but make sure to use enough to cover the meat.
1½ liters beef stock
Place into 350F oven for 2½ hours or until for tender.
You can use the braising liquid as a sauce, but if you want it to be more concentrated, cook it down on a pan with some dark soy sauce and a corn starch slurry to thicken.
Serve with mashed potatoes and green onions.