1 to 2 tablespoons oil
1 teaspoon mustard seed
1 tablespoon coriander powder
1 teaspoon cumin powder
1/2 teaspoon chili pepper powder, to taste
1/2 teaspoon turmeric
salt, to taste
1 tablespoon panela or jaggery sugar*
1 tablespoon tamarind paste
1 to 2 cups water
1 pound (500 g) white potatoes, peeled and in 2" cubes
1. In a pan over medium heat, add and heat oil. Add mustard seeds; heat until they crackle.
2. Add remaining spices (coriander powder, cumin powder, chili pepper powder, turmeric, and salt); stir for a few seconds to temper.
3. Stir in sugar, tamarind paste, and 1 cup of water; bring to a boil.
4. Add potatoes; cover and simmer until potatoes are cooked through, adding more water if needed.
* Panela is unrefined whole-cane sugar that is sold in block form, and is used more often in Central and South America.
Jaggery is unrefined whole-cane and/or date sugar that is sold in block form, and is used more often in Asia, Africa, and the Caribbean.
If you cannot find panela or jagggery sugar, 2-1/4 teaspoons of white sugar + 3/4 teaspoon molasses should be a sufficient substitute.