3 pounds Asian eggplants, cut crosswise into 1/3-inch thick rounds
1 3/4 teaspoons salt
1 garlic cloves, chopped
1 tablespoon ginger, minced
2 teaspoons jalapeno pepper, chopped, include seeds
1 teaspoon mustard seeds (yellow or brown)
1 teaspoon cumin seeds
1/2 teaspoon turmeric
3 tablespoons vegetable oil
1 onion, halved and thinly sliced
1 3-inch cinnamon stick
3/4 cup water
1 tablespoon packed brown sugar
3 tablespoons chopped fresh cilantro
1/4 cup roasted cashews, chopped
Toss eggplant with 1 teaspoon salt in a colander set over a bowl, then drain for 30 minutes. Rinse eggplant, then drain, pressing gently on eggplant to extract any excess liquid.
While eggplant drains, mash garlic, ginger, and jalapeño to a paste with 1/2 teaspoon salt using a mortar and pestle, then stir in mustard, cumin seeds, and turmeric.
Heat oil in 5-quart heavy pot over medium-high heat until hot but not smoking, then sauté onion, stirring occasionally, until softened and golden, 8-10 minutes. Add spice paste and cinnamon stick, then reduce heat to medium and cook stirring, 1 minute.
Add eggplant and cook, stirring, until it begins to soften, about 3 minutes. Stir in water, brown sugar, and remaining 1/4 teaspoon salt and simmer, covered, stirring occasionally, until eggplant is tender but not falling apart, 20 to 25 minutes. Season eggplant with additional salt.
Discard cinnamon stick and serve eggplant sprinkled with cilantro and cashews.