Slice onions, prep scallions
Mix sauce ingredients and whisk well, mirin, sake, tamari, honey, dashi
Add onions to a pot, add sauce mixture, and bring to a simmer - around medium heat
Simmer onions for about 3-4 minutes, or until onions start to go translucent
Add sliced beef, simmer until cooked through (~1 min)
Serve over rice, garnish with optional toppings
