Take a pressure cooker and add in roughly chopped potato, carrots, cauliflower and peas. Pour in water and pressure cook the veggies along with turmeric and salt for 3 whistles.
Once the pressure settles, strain the stock and keep it aside. Mash the veggies and set aside.
Heat oil and butter in a pan. temper with cumin seeds and add in finely chopped onion, green chillies, ginger garlic paste along with crushed kasuri methi.
Saute for 5-6 minutes or until the onions turn translucent with a crispy finish.
Add in tomatoes along with green and red capsicum and saute that for few minutes. Adding red capsicum is optional it is mainly added to give slight sweet tinge. You may skip add a pinch of sugar instead.
Add in turmeric powder, kashmir chilli powder, pav bhaji masala powder and salt. Saute until the masala powders blend well with the veggies. (3-4 min)
Now add in the mashed veggies and stock as well and mix well.
Add salt and simmer the veggie mash until desired consistency.
Garnish with coriander leaves.
Bhaji is all ready!
Now cut the Pav buns into half and generously apply butter. Toast it on a tawa until the inner side gets golden and crisp.
Now Pav Bhaji is ready to be served. Serve Bhaji topped with raw onion, dollop of butter along with toasted pavs (buns), raw onions, coriander and lemon wedges.