Tomato nabe is a hotpot with tomato soup. It may sound unauthentic, but Japanese curiosity helped to evolve traditional nabemono (hotpot dishes) to many unexpected but delicious dishes.
Tomato nabe is quite popular in Japan for years by now. It is basically extra hearty tomato soup cooked in a clay pot (donabe). There is no traditional way of cooking it, you can add any ingredients as your heart desires. I used chicken broth, chicken wings, and chicken sausage with many vegetables in my fridge, you can also use seafood or just vegetables.
Nabemono is the ultimate one pot dish. You can cook and serve in the same pot. Cooking time is short and cleaning is easy as well. Leftover soup can make great risotto by adding rice.