The Tamil words milagu tannir mean "pepper-water," so it is not surprising this vegetable soup has a peppery bite. You can add 4 tablespoons of red lentils, if you so desire. The soup is fairly thick but may be thinned out with as much stock as you wish. In its thick version, it makes a very good sauce for hard-boiled eggs. Serve as a first course or a light meal with crusty bread, fried croutons or plain rice. Offer lime wedges on the side.
Put the peppercorns, coriander seeds, cumin seeds, and fennel seeds in a small cast-iron frying pan and set over medium-high heat. Stir and roast until the spices emit a roasted aroma and some turn a shade darker. Empty into a plate to cool, then grind in a clean coffee grinder or other spice grinder. (It is a good idea to sift the ground spices through a fine sieve, stirring them about with a spoon as they pass slowly through the mesh. This is not absolutely necessary, but it makes for a finer soup.) Add the turmeric and cayenne to the spice mixture.
Put the chickpea flour in a bowl. Slowly add 2 tablespoons of the stock, mixing as you go. Add another 4 cups of stock and mix.
Combine the chickpea flour mixture, spices, all the vegetables, the curry leaves, garlic, onion, and ginger in a large pan and bring to a boil. Cover, turn the heat down to low, and simmer for about 50 minutes, or until all the vegetables are tender. Blend the soup in a blender in several batches, if necessary, and then press through a coarse sieve. Return the soup to the soup pan, add the coconut milk and salt, and bring to a simmer. Simmer gently for 2 to 3 minutes to blend the flavors; thin out with more stock, as needed. Serve hot with lime wedges.
Recipe courtesy of Madhur Jaffrey, World Vegetarian, Clarkson Potter, 1999