Wash and chop cauliflower into medium size pieces and then soak in luke worm water for 10 minutes. Add turmeric or little baking soda in the water to remove the worms and impurities from the cauliflower if any.
Peel and cop the potatoes into medium size pieces and keep aside.
Grind tomatoes and make a fine puree.
Heat oil in a heavy bottom pan and add the cauliflower florets and shallow fry till few brown spots appear on the pieces and then remove from the pan.
Now add potato cubes in the same pan and shallow fry till few golden spots appear on the pieces , remove from the pan and keep aside.
Now add cumin seeds in the same pan when it start to crackle then add all the tempering ingredients.(if there is no oil left in the pan after shallow frying the vegetables then add 2.5 tbsp oil in the pan and when it become hot then add the cumin.)
Now add tomato puree, ginger ,salt and all the dry spices and cook till it tomato become soft and mushy.
Now add the shallow fried vegetables and the green chilies and stir fry for 2 minutes so all the masala get mixed with the vegetables.
Add 3 cups of water and mix well. Cover the pan with the lid and cook on medium to low heat till done.
OR
If Making it in the pressure cooker then follow the same steps and after adding everything and the water , pressure cook it for a whistle.