Combine lamb with chile powder, turmeric and salt. Marinate for at least 30 minutes.
Bring 6 cups of water to a boil with the channa dal, chiles, salt and tomato. Bring to a boil. Simmer and cook until peas are tender, about 45 minutes. Puree using an immersion blender. ( I like it a bit chunky but you can puree completely smooth in a food processor or blender if you prefer)
Combine the cinnamon, cloves, caraway and cardamom seed in a spice grinder. Grind until you have a fine powder.
In a large pot, heat oil. Add cumin seed, onion, dried chiles and curry leaves. Saute until onions are golden. Add ginger garlic paste and lamb. Stir fry for 3-4 minutes. Add masala powder and 2 cups of water. Bring to a boil and simmer for 1 hour, until meat is tender.
Add bottle gourd and cook for another 10 minutes.
In a small bowl, pour the boiling water over the tamarind and let sit for 10 minutes. Strain, pressing all of the liquid out of the tamarind paste and discard the paste.
Add tamarind water and pureed dal. Cook for another 5 minutes.