Prepare the ingredientsCut the onion in half, then slice it thinly. Grate the ginger — you can also use pre-grated or chopped ginger as a shortcut.
Prepare the beefRoughly cut the shaved beef into about 2-inch pieces so they’re easier to eat and cook evenly.
Make the sauceIn a large skillet or medium pot, combine water, sugar, soy sauce, mirin, sake, and optional dashi powder. Stir well until the sugar dissolves completely, but don’t turn on the heat yet.
Add the beef and onionsLoosen the sliced beef as you add it to the skillet — this helps prevent the meat from clumping together as it cooks. Then place the sliced onions on top of the beef and add the grated ginger. Stir lightly to mix.
SimmerCover with a lid and cook over medium heat for about 5–8 minutes. Occasionally skim off any foam or impurities that rise to the surface for a cleaner flavor.
ServeServe the simmered beef and onions over bowls of steamed white rice. Garnish with beni shoga (pickled red ginger) and chopped green onions. Enjoy!