Macadamia nuts and halibut work well together. Ground up with panko, garlic and parsley, they bake into a crisp golden crust with no frying involved.
The sauce takes about five minutes and you can make it while the fish is in the oven. Butter, cream, lime juice. That is all it is. Halibut is what we use, but lingcod or Pacific cod are fine substitutes.
Heat the oven to 425°F. Line a rimmed cookie sheet with parchment paper. Pat the halibut filets dry with paper towels. Wet fish steams under the crust and it will not crisp. Get the flour, eggs, crumb mixture and butter out now, before your hands are covered in breading.
Pulse the macadamia nuts in a food processor until they look like coarse sand. You can chop them by hand if you would rather, just get them fine. Big pieces burn before the fish is done and they fall off when you cut into it. Put the nuts in a wide bowl with the panko, garlic and parsley. Pour the melted butter over and stir. When it is ready the mixture feels damp and holds its shape if you squeeze a handful.
Set out three shallow dishes. Flour, then beaten egg, then the crumb mixture. Take one filet, press it into the flour, turn it over, then lift it and tap off everything loose. You want a thin dusting and nothing more. Heavy flour is the reason breading comes off in one piece when you cut into it.
Put the floured filet in the egg and turn it once. Lift it and hold it over the bowl a few seconds so the extra drips off. If egg pools on the fish the crumbs clump instead of coating it. Use one hand for the dry dishes and the other for the egg if you can, or you will end up with a paste on your fingers that gets into the crumb bowl.
Lay the filet in the crumb mixture and spoon more over the top. Press it on. The butter in the mixture makes it stick, and packing it down is what gets you a solid crust instead of crumbs all over the pan. Flip it once more and get the edges and the sides, which are easy to miss.
Put the filets on the parchment with an inch or so between them. If they touch, steam gets trapped and the crust goes soft in those spots. Use two pans if six will not fit. A wire rack set inside the sheet pan works even better, since air gets underneath and the bottom crisps too.
Bake at 425°F for 15 to 20 minutes. You are looking for a golden crust, and the thickest filet should flake when you test it with a fork. Go by thickness, not the timer. A thin tail piece might be done at 12 minutes while a thick center cut takes the full 20, so check early and pull them as they finish. If the crust is getting dark before the fish is cooked, lay a piece of foil loosely over the top.
Melt the butter in a small saucepan over medium heat. Do not let it brown. Whisk in the cream, then add lime juice a little at a time and taste as you go, because limes are inconsistent. Turn the heat to low and leave it there until you are plating. Whisk it again before it goes on the plate if it looks like it is separating.
Put the sauce down first and set the halibut on top of it. Pouring sauce over the fish softens the crust before it reaches the table. Add chopped parsley and a lime wedge on the side. Serve it right away.
The nuts are rich and a little sweet, the halibut is mild, and baking rather than frying keeps the fish light while the crust still browns properly. Roasted asparagus or green beans work as a side. Rice or polenta is good if you want something to catch the extra sauce. For wine, pour something crisp and unoaked.
