I get very confused about the difference between a sweet potato and a yam. While this recipe calls for sweet potatoes I always use the darker orange fleshed potato when I make this which might be a yam, or at least labeled as such in the store. Quite frankly I am not sure it would matter what you used, including pumpkin. This is a tasty South Indian dish. The recipe below is adapted from Betty Crocker's Indian Home Cooking by Raghavan Iyer, my Indian cooking mentor. While quite an oxymoron, this is one of the best Indian cookbooks ever! The original recipe calls for 1/4 teaspoon asafetida, also know as hing. Asafetida is a spice which has a pungent, unpleasant smell in the raw form, powder or block. Once cooked it delivers a smooth flavor similar to leeks. Asafetida is never gluten free! In the powdered form it is laced with wheat flour to keep it from clumping. Some speculation has been made that in the brick form it might be GF. According to Raghavan, who did some research for me and translated the ingredients on a number bricks, it is not GF. I asked Raghavan to look into this for me after getting very very sick from eating something made with brick hing.
Sweet Potato Curry
1 tablespoon vegetable oil
1 teaspoon black or yellow mustard seeds (I always use black)
2 tablespoons yellow split peas, chana dal
1 pound sweet potato, peeled and cut into 1/2 inch chunks
8 fresh karhi leaves or two tablespoons chopped fresh cilantro
1 teaspoon Tangy Sambhar Powder
3/4 teaspoon salt
1/2 cup water
Heat oil and mustard seed in a deep 12 inch skillet over medium high heat. Once seeds begin to pop, cover pot and wait until popping stops. Add split peas, stir-fry for a minute or two, until the peas are golden brown. Add remaining ingredients except water; stir fry 1-2 minutes. Stir in water, bring to a boil, reduce heat, cover and simmer 5-7 minutes or until sweet potato is tender.
Tangy Sambhar Powder
1/2 cup dried red thai chilies
1/4 cup dried yellow split peas, chana dal
2 tablespoons sesame seed
1 tablespoon tamarind pulp or grated lime or lemon peel
1 tablespoon coriander seed
1 teaspoon cumin seed
1 teaspoon black peppercorns
Mix all ingredients in a small bowl. Heat 6 inch skilled over medium high heat. Place mixture in skillet and roast 1-2 minutes, stirring constantly until seeds crackle, spices turn one shade darker and mixture has a nutty yet pungent aroma. Transfer to a bowl and cool completely. Place roasted spice blend into a spice grinder in batches, about 3 tablespoons at a time. Grind until mixture looks like the texture of finely ground pepper. Store in an airtight jar at room temperature for a month. After a month or so it starts to loose its full flavor.