Peel the potatoes, cut them into quarters, and soak them in cold water for 15 minutes.
Peel and cut the onion into wedges and chop the carrots into rolling wedges.
Cook konjac noodles in the boiling water for 1 minute and put them in cold water.
In the meantime, combine the broth ingredients together. Set aside.
Heat up oil in a pot and cook ground beef (or sliced beef) on medium heat with sake and salt & pepper until the meat is brown.
Add onions and carrots and cook for about 5 minutes.
Add the broth ingredients, potatoes, 2 cups of water, and konjac and bring to boil.
Once boiling, skim the scum and foam. Make sure all the ingredients are flat and covered by broth. Add water if it's not covered.
Place aluminum foil directly on top of the food and simmer with low heat for 15 minutes.
Take off the aluminum foil, add soy sauce and simmer for 10 minutes.