Take a pan and heat it on medium heat, once hot, add oil and add mustard seeds, allow it to sputter.
Next add cumin seeds, and next add onions and add a little salt and cook until the onions are softened.
Next add in the veggies with little salt and cook them with a lid on for 5 minutes.
Next add the tomatoes and cover and cook until the tomatoes are softened
Next add the masala powders (turmeric, red chilli powder, cumin powder, chat masala) sauté well.
Next add in the tomatoes purée and cook for a few more minutes, check salt and add more if needed.
Finally add the Corriander leaves and turn off the flame.
Slice the bread and butter it on both sides, toasts it on another pan and add the prepared masala on one side and let it cook for a few mins until toasted. Serve hot.