Tomato-Bottle Gourd soup

I tried this soup from My Tasty Treats and just added onions extra to her ingredients.
It tasted very nice and her recipe was very simple and easy to make.
It is very healthy too.
Ingredients
2 Tomato
2 carrots
1 Onion
1/2 cup Bottle gourd
1 table spoon Butter
pepper to taste
Red pepper flakes to taste
salt to taste
water

Method
In a pressure cooker add the vegetables,salt and allow it to cook up to 2 whistles based on each cooker.
Transfer it to mixer and let it cool before churning.
Grind it and sieve it if required.
Add the butter and pepper and mix well.
Serve hot.