3 pounds boneless, skinless chicken thighs, trimmed
2 medium onions, halved and thinly sliced
8 garlic cloves, thinly sliced
16 thin slices peeled fresh ginger (about 1 ounce)
2 tablespoons curry powder, preferably Madras
1 teaspoon ground coriander
1 teaspoon ground cumin
Coarse salt
2 packages frozen green peas (10 ounces each)
2 cups unsweetened coconut milk
1/2 cup toasted cashews (optional, for serving)
1/4 cup cilantro leaves (optional, for serving)