Heat butter in a pan, add a pinch of asafoetida powder. Add ginger garlic paste. Cook for 2-3 minutes till the raw aroma goes away. Add chopped onions and cook for a few minutes till these turn translucent.
Add tomato puree, and cook till the tomatoes are nicely cooked, and start leaving butter on the sides.Add chopped green chillies.
Add a little salt, red chilli powder, deghi mirchi powder, coriander powder, Pav bhaji masala. Mix together all the masalas, in the tempering.
Add mashed veggies. Use a masher to mix together the veggies with the tempering. .Check the consistency. It should be a little runny, and not too thick.
If required add water at this stage to adjust consistency.
Cover and let it cook for another 10 minutes.Once done check and adjust the seasoning. Add finely chopped coriander.