Place spinach in a large bowl with 2 tbsp water. Microwave on high for 3 minutes. When cool enough to handle, squeeze out as much of the moisture as possible. In another bowl, microwave cabbage leaves with 2 tablespoons of water on high for 5 minutes. Drain.
Divide spinach into 8 portions. Place each portion on a cabbage leave and roll tightly. Cut each roll into half cross-wise.
Pour stock into a large flame-proof earthenware casserole or cast iron pot. Add chicken, shiitake mushrooms, and cabbage-spinach rolls. Cook for 3 to 4 minutes over medium heat, skimming off scum appearing on the surface.
Add low fat milk, carrot, shirataki, soy sauce, sugar, and salt and continue to cook for another 5 to 6 minutes.
Serve immediately.
Notes
Nabe is best cooked at the table with a portable cooking unit. If you are using a small fondue unit, you may want to cook the first part using chicken stock on the stove. Then transfer to the table and finish cooking by adding milk and the rest of the ingredients.