Why it works
Swordfish's firm, dense flesh stands up beautifully to direct grilling without flaking apart. A properly preheated grill to 400°F creates a sear that locks in moisture while the interior stays tender. The brown butter sauce—nutty, tangy, and briny—offers bright acidity and richness that complements grilled seafood without overshadowing its natural flavor.
This cook is built for easy pitmasters running a gas setup, but the real win is that the method stays adaptable if your fire drifts or your timing gets crowded.
- Preheat a gas or charcoal grill to 400°F for about 10 minutes. Oil the grill grates well to prevent sticking. The grill is ready when it holds a steady, high temperature.
- Pat swordfish steaks completely dry with paper towels. Season both sides evenly with kosher salt and black pepper. Brush lightly with olive oil.
- Place swordfish steaks directly on the hot oiled grates. Close the lid and grill without moving for 3–4 minutes. A golden crust will form and the fish will release more easily from the grates when ready to flip.
- Using a wide fish spatula, carefully flip each steak. Grill the second side for 3–4 minutes, checking the thickest part with an instant-read thermometer as it approaches doneness. Target an internal temperature of 130–135°F; the fish will continue cooking as it rests.
- Transfer grilled steaks to a warm platter and tent loosely with foil. Let rest for 2–3 minutes.
- While swordfish rests, melt butter in a small skillet over medium heat. Swirl the pan frequently and watch carefully until the butter foams, then begins to smell nutty and turns light golden-brown (2–3 minutes). Do not let it burn. Immediately remove from heat.
- Add lemon juice, lemon zest, and drained capers to the brown butter. Stir gently and taste. Add more lemon juice if desired. Do not reheat; serve at room temperature.
- Arrange swordfish steaks on plates. Spoon brown butter caper sauce generously over each steak. Garnish with fresh parsley if desired. Serve immediately.