Whisk miso into the water until dissolved; set aside.
Heat the sesame oil in a frying pan or wok over medium-high heat. Cook the white parts of the green onion until lightly colored and fragrant, 30 seconds to 1 minute. Stir in the ground meat, and cook for a few minutes until nearly done.
Gently stir in the tofu with the miso paste. Bring to a simmer, and cook for a few minutes to warm the tofu.
Sprinkle with the green parts of the green onions before serving.
