How to Grill Fish: Grilled Swordfish with Grapes & Onions

How to grill fish. Grilled Swordfish

I’m not a grill master. Give me a steak and my first impulse is to sear it hot and fast on the stove. But when it comes to the question of how to grill fish, for some reason I feel more at home. Though I realize a lot of people find seafood (grilled and otherwise) intimidating. For what it’s worth I’d thought I’d offer a few tips on how to grill fish.

There are a lot of reasons to fear fish and live fire. Good seafood is expensive. There’s real stress in watching big bucks go up in flames. It’s difficult partly because seafood can be delicate and hard to maneuver. It easily sticks to the grill or breaks up into unattractive clumps. Some of the smaller types, like shrimp and scallops, can overcook in the blink of an eye– or fall through the grates into the fire. So learning how to grill fish is probably a good idea.

How to Grill Fish

  • Return it to the sea: Brining fish for about 1 hour in a simple mixture of 1/4 cup salt and 6 cups iced water is a great way to get fish seasoned all the way through. It also helps keep fish from drying out when cooked over high or direct heat– as in grilling. But it does something else. It firms the flesh, making it cook up a bit meatier and less likely to fall apart on the grill. Once the fish has been brined, rinse and dry it well. Then let is rest in the refrigerator at least 2 hours and up to 6 hours. Marinating can have the same effect, though marinades can be high in acid so please don’t marinate most types of fish more than 15 or 20 minutes. The acid may “cook” the flesh more than you’d like for grilled preparations.
  • Learn to love the skin it’s in: Consider leaving the skin on the fish (if it comes that way). That way when you grill it it’s more likely that the fish will stay together.
  • Cleanliness is next to fishiness: You have to clean your grill and I shouldn’t have to tell you that. Heat it up to carbonize any food remnants, and then scrape off the debris.
  • Stick-to-it-ive-nessOne of many people’s biggest fears about grilling fish is having it stick to the grill. But fear not, proper preparation is key– not only should you brush your fish with oil before grilling, you should also brush the grates. Brushing the grates alone isn’t enough. Once you’ve laid the fish on the grill don’t move it until it’s properly seared. Once seared it can flipped without it sticking or tearing apart.
  • All creatures great and small: If you’re working with scallops, little shrimp or even small chunks of meatier fish I suggest you grill them on skewers. That’s skewers plural you see. To keep food from slipping off during cooking and turning, I often use two parallel skewers rather than a single skewer. This trick assures that even small pieces of seafood will lay flat and flip easily. However, single flat metal skewers are a good choice too. Just remind diners how hot they can get.
  • Know when to stop: Don’t overcook the fish, it’s a waste of the poor creature’s life. The general rule is that most fish will take 7 to 8 minutes to cook all they way through per inch of thickness. This translates into about 3 to 4 minutes per side. If you’re cooking a whole fish the accepted number is 10 minutes per inch. Some fish, like salmon and tuna, are often better left rare on the inside. Follow your preferences in these cases.

Tips on how to grill fish in general are fine. The best advice I can give is to accompany grilled fish with friendly flavors. In this case a touch of sweetness and a luscious texture compliment the smoky, meaty elements in my recipe for Grilled Swordfish with Sautéed Grapes and Sweet Onions. This quick fish dish takes hardly more effort than lighting the grill. Follow my tips on how to grill fish and give it a try. GREG

How to grill fish. Brined Swordfish with grapes

How to Grill Fish

Grilled Swordfish with Sautéed Grapes and Sweet Onions 

Print This Recipe Total time Yield 4Published

The brining is optional but it does improve the taste and texture of most low fat grilled fish dishes.

grilled swordfish with grapes and sweet onions


  • ¼ cup kosher salt (optional)
  • 2 cup water (optional)
  • 4 cup ice (optional)
  • 4 (6 oz) swordfish steaks
  • ¼ cup extra-virgin olive oil (separated)
  • 2 sweet onions (such as Walla Walla or Vidalia) thinly sliced
  • 2 clove garlic (peeled and smashed)
  • 2 sprigs fresh rosemary (plus more as garnish)
  • 2 tablespoon red wine vinegar
  • 2 teaspoon honey
  • sea salt and freshly cracked black pepper (as needed for seasoning)
  • 2 cup seedless red grapes


Brine the fish: Combine kosher salt and 2 cups water in a large mixing bowl and stir to dissolve the salt; add ice. Place the swordfish fillets in the brine and leave for 1 hour. Remove the fish from the brine, dip briefly in salt-free ice water and dry it thoroughly with paper towels. Lay the fish out flat on parchment-lined baking sheets; cover and refrigerate for about 4 hours (ideally). This step is optional.

Prepare the grapes and onions: Heat 3 tablespoon olive oil in a large sauté pan set over medium-high heat. Add the onion slices, garlic, rosemary, vinegar and honey; cook until the onions soften, about 4 minutes. Lower the heat to low and season the onions with salt and pepper. Cover the pan and cook until tender, stirring occasionally, about 10 minutes. Add the grapes, cover the skillet again and cook until they begin to split, about 5 minutes. 

Grill the fish: Meanwhile, cut out the bloodlines on the fish if necessary. Brush the swordfish with the remaining olive oil and season with more salt and pepper. Grill or broil the fish until just cooked through, 3 to 4 minutes per side. 

Plate the dish: Discard the rosemary sprigs and smashed garlic from the sautéed grape mixture, then spoon some onto each of warmed warmed plates. Top with swordfish, garnish with a bit of fresh rosemary and a drizzle of the accumulated pan juice and serve immediately.