With a mortar and pestle crush the black pepper, cinnamon, cloves and cardamom.
Heat oil in a deep bottom pan drop in the crushed spices let them splutter.
Add the onion, ginger, garlic, curry leaves and green chilli and sauté for a few minutes till the onion becomes soft and transparent. Take care not to brown the onions.
Add the cubed vegetables and mix well.
Add thin coconut milk and salt, bring to boil.
Reduce heat and let the mixture simmer until vegetables are tender.
Add thick coconut milk and cook for 5 more minutes & remove from fire.
Garnish with curry leaves fried in coconut oil or ghee.
Traditionally this is served hot with appam, puttu, roti etc;
Notes
If you want to make the gravy very thick, add 6-7 cashew nuts ground to a paste.