Heat up a medium to large size pot and add the sesame oil. Once hot, add the onion and garlic and allow to caramelize.
Add kimchi, tomatoes, and chili paste. Stir and let cook for a few minutes.
Add in vegetable stock and bring to a boil.
Add in the soft tofu and break it into pieces with a spoon. Let the stew cook and simmer for 10-15 minutes to let the tofu absorb all of the flavors!
Serve over rice or by itself - either is delicious!