Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
     1/2  cup           red gram dal
   2      cups          water
                        a lemon-sized piece of tamarind pulp
   1      cup           hot water
   2                    green chiles -- sliced
   1      cup           mixed vegetables -- chopped (e.g. radish
                        -- onion, okra, eggplant
   1      cup           water
                        salt -- to taste
     1/2  teaspoon      ground turmeric
   3      teaspoons     sambar powder
   1      tablespoon    rice flour -- optional
   2      tablespoons   extra water -- optional
   1      small bunch   coriander leaves -- chopped, for garnish
                        *** FOR TEMPERING ***
   1      tablespoon    oil -- (to 1 1/2 tbsp.)
   1      tablespoon    brown mustard seeds
     1/2  teaspoon      asafetida powder
     1/2  teaspoon      fenugreek seeds
     1/2  teaspoon      cumin seeds
   1                    red chiles -- halved
                        a few curry or bay leaves

Preparation:

Wash gram dal well. Drain. Place dal in a heavy saucepan. Cover with 2 cups water and bring to a boil. When boiling, cover pan with a lid, leaving slightly ajar. Stir several times during the last 30 minutes of cooking. Set dal aside without draining. Soak the tamarind pulp in 1 cup hot water for 15 minutes. Strain the tamarind water into another container, squeezing as much liquid as possible out of the tamarind pulp. Discard the pulp. Set the juice aside. Select enough vegetables to fill approx. 1 cup when chopped. Peel and prepare as necessary. Chop into 1/2 in. pieces. Set aside. TEMPERING: Heat 1 1/2 tablespoons oil in a heavy saucepan. Add the mustard seeds, asafetida powder, fenugreek seeds, cumin seeds, halved red chile powder, and a few curry leaves. When the mustard seeds splutter, add the slit green chiles and chopped vegetables. Sauté' for a couple of minutes. Add the tamarind juice, 1 cup water, salt to taste, ground turmeric, and sambar powder. Cover and simmer over low heat until the vegetables are tender. Add the undrained cooked dal. Simmer for 5 minutes, until thoroughly blended. If the sambar needs to be thickened, make a smooth paste of the rice flour in 2 tablespoons extra water. Add to the sambar and cook for 2 - 3 minutes. Garnish with the chopped coriander leaves. Serve hot with rice. Notes: When two or three vegetables are used, there is a subtle blending of the different flavors of each vegetable. For a more distinctive flavor, make the sambar with only one type of vegetable. If potato is used singly, reduce the amount of oil added while tempering. Vegetables such as sweet pepper, onion, eggplant, okra, etc. will require a little more oil. From Dakshin: Vegetarian Cuisine From South India by Chandra Padmanabhan