Ingredients

  • 2 teaspoons coriander seeds
  • 2 teaspoons cumin seeds
  • 1/3 cup roasted salted cashews
  • 1 1/2 teaspoons turmeric
  • 1 tablespoon finely grated fresh ginger (preferably using a Microplane)
  • 1 tablespoon finely grated fresh garlic (preferably using a Microplane)
  • 1 medium tomato, halved crosswise
  • 1/4 cup vegetable oil
  • 6 to 8 whole dried arbol chiles, stemmed
  • 1 medium onion, halved and thinly sliced
  • 2 small red sweet peppers, cored and seeded, then halved; or 1/2 larger red bell pepper, cut into 1/2-in. slices
  • 2 small yellow sweet peppers, cored and seeded, then halved; or 1/2 larger yellow bell pepper, cut into 1/2-in. slices
  • 2 small orange sweet peppers, cored and seeded, then halved; or 1/2 larger orange bell pepper, cut into 1/2-in. slices
  • About 1/2 tsp. salt
  • 1 can (13.5 oz.) coconut milk
  • 1 tablespoon tamarind concentrate
  • 1 tablespoon packed light brown sugar
  • 1 1/2 pounds albacore tuna loin, cut into 3/4-in.-thick medallions
  • 1 1/2 to 2 tbsp. lime juice
  • 1 cup loosely packed mixed fresh herb leaves, such as basil, cilantro, and mint, torn if large

Method

  • Put coriander and cumin in a spice grinder or clean coffee grinder and grind until fine. Transfer to a bowl. Put cashews in grinder and grind into a paste. Add to bowl and stir in turmeric, ginger, and garlic.
  • Grate tomato on the large holes of a box grater into another bowl, discarding skin. Set aside.
  • Heat oil in a large, straight-sided skillet over medium heat. Crack half the chiles open and add to pan along with onion. Cook, stirring, until onion softens, 2 to 3 minutes. Add peppers and continue cooking until vegetables begin to soften, 3 to 4 minutes. Add spice paste and 1/2 tsp. salt and cook, stirring often, until paste begins to fry, about 2 minutes. Add grated tomato, coconut milk, tamarind, brown sugar, and 3 tbsp. water; add 1 to 2 tbsp. more water if it seems thick. Reduce heat to medium-low and simmer 5 minutes, uncovered.
  • Tuck tuna pieces into sauce and gently simmer, covered, turning fish once, until almost cooked through, about 3 minutes. Stir in lime juice and season to taste with salt. Transfer to shallow bowls and top with herbs.
  • *Find tamarind concentrate at Indian markets, or add a little extra lime juice instead.