Turn the saute button of instant pot on.When its displays hot ,add butter to it .
Add chopped onion to the melted butter and saute it for 1 minute or till it looks transparent .
Add ginger garlic paste to it and saute till all the raw smell is gone .
Add all the vegetables ,little salt and turmeric to it .Saute for 1 minute .If it feels like sticking to the bottom scrape it with the spatula.
Add 1.5 cups of water and cook on high pressure for 7 minutes.
Open the lid by releasing the pressure manually or if you are too scared let it release naturally.Take a potato masher and mash all the vegetables in to a smooth mash.
Now add tomato paste ,pav bhaji masala ,kashmiri red chili powder and mix it well.
Let it cook for 2 minute .Stir it continuously to avoid sticking .
If it looks too thick for you ,add little bit of warm water .
Add 2 tbsp of butter to it .If you are making it vegan do not use any thing at this time .
Cook it again for 1 minute .Bhaji is ready to enjoy with pav.
Brush dinner rolls /Pav with butter and toast them till they look golden.
Serve with chopped onion,cilantro and lemon wedges.
Enjoy your pav Bhaji.