1 (1-inch) piece peeled fresh ginger
3 scallions (white and green parts), cut into large pieces
1 cup fresh mint (leaves and some stems)
1 cup fresh cilantro (leaves and some stems)
1 ¿4 cup plain low-fat yogurt
1 jalapeno, stemmed (ribs and seeds removed if you don't want it too hot)
1 tablespoon freshly squeezed lime juice
1 ¿2 teaspoon kosher salt
1 to 2 tablespoons water, if needed
1 teaspoon vegetable oil
1/2 teaspoon Madras-style curry powder
1/2 teaspoon kosher salt
Freshly ground black pepper
4 (6-ounce) swordfish steaks
Basmati rice, for serving, optional