In a medium pot that will fit the block of tempeh, combine the tempeh and the vegetable broth and bring to a boil. Immediately reduce to heat and simmer gently for 15 minutes. When done, dice into small cubes and set aside. (Discard the liquid or keep it for cooking rice to serve with this dish)
In a large skillet, warm the oil and then add the diced potatoes and sliced carrots. Adjust heat to medium high and cook for 10-15 minute until the vegetables have a nice, golden color to them.
Add in the onions and tempeh and continue sauteing for about 3 minutes. The pan will be getting pretty dry and that's okay. Do NOT add any more oil.
Add the cabbage, garlic, ginger and mushrooms, then give it a quick stir. The pan should be very dry.
Now deglaze with the mirin and tamari.
Stir for a few minutes to coat everything in the glaze.
Please note that the nutrition data given here is a ballpark figure. Exact data is not possible.