Shell the beans from the pods and wash well. Finely chop onions and make tomato puree.
Heat a pressure cooker with oil, add mustard, and fennel seeds, and let it splutter.
Next, add the finely chopped onions, and curry leaves and let the onions brown a little.
Once the onions are brown, add ginger garlic paste, and saute well.
Add peeled and cubed potatoes to the pan and combine everything well.
Simmer for a while as the potatoes get browned.
Add tomato puree, and mix well.
Now add the spice powder one by one and mix well.
Cook on high flame until the masala is well mixed.
Simmer for 5 mins, add the butter beans now.
Mix well and let it simmer for a few minutes.
Add the ground coconut masala, and mix well along with water as required.
Cover with lid and pressure cook for 1 or 2 whistles as needed.
Once the pressure falls, remove the lid, add chopped coriander leaves and bring to a boil
Serve with parottas.