Boil the cashews for 15 minutes, drain and blend with the milk and peanut paste. Set aside.
Finely chop the onion, garlic and a small piece of ginger. Cut the seitan into bite-size pieces, and the sweet potato into dice.
In a large pan, sauté the onion on medium heat for 5 minutes in the melted butter. Meanwhile, mix the minced garlic with the ginger, garam masala, ground coriander and cayenne. Add to the pan and sauté for another 2 minutes. Add the seitan and cook for another 5 minutes.
Add the sweet potato, cover in broth and simmer for 15 minutes. When the sweet potato is soft, add the chopped tomato and cashew cream. Stir well and serve with brocoli and fresh coriander with jasmine rice.