In a blender or food processor, blend the chopped tomatoes, onion, and soaked cashews until smooth.
In a skillet or kadhai, heat the vegan butter or oil over medium heat. Add cumin seeds and let them splutter.
Add the tomato paste and sauté for 1-2 minutes.
Add the blended tomato-onion-cashew mixture to the skillet and mix well. Add water if the mixture is too thick.
Add garam masala powder, coriander powder, turmeric powder, red chili powder, and salt to taste. Mix everything well.
Add the cubed tofu to the skillet and mix well. Cook for 5-7 minutes or until everything is well combined and heated through.
Garnish with chopped coriander leaves and serve hot with roti or rice.