Prepare the ingredients: peel and cut the Potato into bite-sized chunks; peel and slice the Carrot on the diagonal; thinly slice the Onion; trim and rinse the Shirataki and parboil for 1–2 minutes, then drain; trim the Snow Peas and set aside.
Heat a heavy pot over medium heat and add a little Neutral Oil. When hot, add the Beef in a single layer and quickly sear until just browned—you only want to color the meat, not fully cook it. Remove and set aside.
In the same pot, add a touch more oil if needed and sauté the Onion until softened and translucent. Add the sliced Carrot and cook for another 2–3 minutes to begin softening.
Return the browned Beef to the pot and add the Potato pieces. Stir everything together so the flavors meld briefly.
Pour in the Dashi until the ingredients are mostly submerged (adjust volume depending on pot size). Add Sake, Mirin, Soy Sauce, and Sugar to the pot, stirring to dissolve the sugar and combine the seasonings.
Bring the mixture to a gentle boil, then lower the heat and simmer partially covered for 15–20 minutes, or until the Potato is tender and the beef is fork-tender. Skim any foam or excess fat from the surface as needed.
Add the prepared Shirataki about 5–10 minutes before the end of cooking so it soaks up the braising liquid and heats through. Taste and adjust seasoning with a little more Soy Sauce or Sugar if desired.
Blanch the Snow Peas quickly in boiling water for 20–30 seconds until bright green, then plunge into ice water to stop cooking. Drain and add the snow peas to the pot just before serving for color and a crisp contrast.
Serve the nikujaga hot in bowls with some of the braising liquid spooned over rice, garnishing with the vibrant Snow Peas on top.
