- 3 tablespoons dried hijiki (seaweed)
- 1 small shallot, finely chopped
- 1 anchovy packed in oil, drained, finely chopped
- 1/2 cup chopped fresh flat-leaf parsley
- 1/3 cup extra-virgin olive oil
- 2 tablespoons drained capers, chopped
- 1 1/2 teaspoon finely grated lemon zest
- 1/2 teaspoon crushed red pepper flakes
- Kosher salt, freshly ground pepper
- 8 6-ounce swordfish steaks
- 2 tablespoons vegetable oil
- Ingredient info: Dried hijiki is available at natural foods stores, many supermarkets, and online sources.
- Place hijiki in a small bowl, add boiling water to cover, and let sit 10 minutes. Drain. (You should have about 1/2 cup.)
- Combine hijiki, shallot, anchovy, parsley, olive oil, capers, lemon zest, and red pepper flakes in a medium bowl; season with salt and pepper. Set salsa verde aside.
- Prepare a grill for medium heat. Rub fish all over with vegetable oil; season with salt and pepper. Grill, turning occasionally, until firm to the touch and opaque throughout, 8-12 minutes. Serve fish with salsa verde.
- DO AHEAD: Salsa verde can be made 2 days ahead. Cover and chill.