Heat the vegetable oil in a large non-stick saucepan.
Add the mustard seeds and once they are popping turn the heat down and add the onion and cinnamon.
Cook the onion until golden around 8 minutes.
Meanwhile using a blender make a fine paste of the ginger, garlic and chillies with 50ml water.
Add this to the cooked onions along with the powdered spices.
Cook until reduced then fry over a low heat for 2 minutes or until the oil is released.
Add the tomatoes and another 100ml water, cook until completely reduced and fry the paste for 4-5 minutes or until the oil comes out on top.
Stir in the coconut milk and 150 ml of water bring to a gentle simmer and allow the flavours to marry and develop for 5 minutes.
Add the tofu and cook until done around 4-5 minutes.
Taste and adjust the seasoning then serve.