Health-conscious cooks are fond of grilling, which imparts rich flavors to foods without adding fat. Fish is also a healthy choice, with its lean flesh and heart-healthy omega-3 fatty acids, so grilled fish is as healthy as it is tasty. Meaty swordfish and salmon stand up easily to grilling, but haddock is a little more delicate. It's still firm enough to grill, but you'll need to handle it carefully and adequately prepare your grill.
Clean your grill's grate thoroughly with a scraper and wire brush, until the rack is free of any crusted-on debris. If necessary, place the grate in a large tub with hot, soapy water and scrub it with non-abrasive nylon scrubbing pads. Dry the rack thoroughly before returning it to the grill.
Oil the rack thoroughly with a rag dipped in a high-temperature cooking oil, such as grapeseed oil, canola oil or safflower oil. Alternatively, spray it liberally with a high-temperature pan spray. Light the grill, close the lid and preheat it to medium-high.
Dry the haddock fillets thoroughly on clean paper towels. Spray or brush the fillets lightly with oil, then season them lightly with salt and pepper or other flavorings you like.
Open the grill. Space your fillets evenly across the rack, with the skin side facing up. Be attentive as the flesh turns from translucent to opaque as it cooks over the grill's heat. Grill the fillets until they are about one-third of the way cooked. This can take four to six minutes, depending on their thickness.
Slide a spatula with a wide, thin metal blade under the first portion. If it's properly seared, it will release from the bars of the grate. Flip the pieces individually, taking care not to break them.
Cook the pieces on the second side for another three to four minutes, or until there's just a hint of translucent flesh left in the very middle of the portions. Remove them from your grill to a serving platter and let the pieces rest for two to three minutes, as they finish cooking in their residual heat.
- On Food and Cooking: The Science and Lore of the Kitchen; Harold McGee
- Serious Eats: How to Grill Skinless Fish Fillets or Steaks
- Skin-on fillets are easier to grill because the skin holds the delicate flesh together. If you have skinless fillets, oil one or more fish-grilling baskets and use those to hold the portions. The basket helps keep them intact and minimizes the risk of sticking to the grill. Or place a piece of well-oiled heavy foil on the grill and cook the fillets on that. Puncture the foil in several places to allow the flames to impart their signature grilled flavor to the haddock.
- Avoid thin fillets if you plan to cook them on the grill. A thickness of 3/4 inch to 1 inch is thick enough to be sturdy on the grill, but thin enough for the portions not to break under their own weight as they're turned.
- Even when you do everything perfectly, pieces will sometimes break up when they're turned. If you're serving company, buy and cook a few extra portions to allow for breakage. Use leftover portions on sandwiches or over salads as a light lunch.
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