Cut the dried kelp into two pieces. Place them in a large pot with the 4 cups (950 ml) of water and let soak for 30 minutes.
Cut the napa cabbage into 1.5-inch (4 cm) pieces. Slice the scallions diagonally into 4-inch (10 cm) lengths. Cut the shiitake mushrooms in half and cut the chrysanthemum leaves in half.
Rinse the shirataki noodles under cold water. Spread them on a cutting board and cut them into three shorter portions. Arrange all the vegetables, noodles, and beef slices on a large serving platter.
Grind the sesame seeds in a mortar and pestle until they look slightly wet. Add the white miso, soy sauce, sugar, and rice vinegar.
Place the pot with the kelp and water on the stove over medium-high heat. As soon as small bubbles appear, remove and discard the kelp. Take 1 tablespoon (15 ml) of this hot broth and stir it into the sesame mixture until smooth.
Transfer the pot of broth to a portable burner on the dining table. Bring the broth to a gentle boil. Pour the sesame sauce and ponzu sauce into individual dipping bowls for each person.
Pick up a slice of beef with chopsticks and swish it in the boiling broth for about 10 seconds until cooked. For food safety, whole cuts of beef should reach an internal temperature of 145°F (63°C) with a 3-minute rest, though these thin slices cook almost instantly.
Dip the cooked beef into the sesame sauce or ponzu sauce before eating. Cook the remaining beef slices, using a ladle to skim off any foam that rises to the surface of the broth.
Add the vegetables and noodles to the enriched broth in small batches. Cook until tender, then dip in the sauces and eat.