Pressure cook bottle gourd near to one whistle with 1/2 cup of water. Now open the pressure cooker immediately. Keep boiled bottle gourd aside.
Heat oil in a pan, add mustard seeds and allow them to pop.
Now add onions and cook until translucent.
Then add garlic and ginger cook for a minute. Now cook until onion is golden brown.

Now lower the flame and add sabzi masala, turmeric, coriander powder, and salt. Cook for a minute.
Now add tomato puree and cook until masala leaves oil.
Add chopped tri colour capsicum, chopped green chilli and cook for 5 minutes until tender on a low medium flame.
Now add boiled lauki (with water) and mix well. Cook for 5 minutes on low flame. Garnish with coriander leaves and serve with hot parathas or steamed rice.