Step 1

Pat sablefish dry.  Sprinkle fillets on both sides with salt and pepper.Allow fillets to rest at room temperature for about 15 minutes. (Cold fish is more difficult to sear.)

Step 2

Add olive oil and half the butter to a heavy pan. Melt butter over medium heat. Place the fillets skin-side down in the pan and cook about 4 minutes, depending on the thickness of the fillets. As the sablefish cooks, the flesh will begin to turn opaque from the bottom up. When the fish has cooked halfway through, it's ready to flip.Avoid touching the fish until the fish is ready to flip.

Step 3

Use a thin metal spatula to test the fish.  If you can slide the spatula under the fish without the fish sticking to the pan, it's ready to flip. If the fillets won't release, give them another 30 seconds. They'll release when they've finished cooking.Cook fish about 4 minutes until done. Timing will depend on the thickness of the fillet. (Watch the sides of the fillets to see when the fish is done cooking. It's finished as soon as there are no more translucent patches and it's fully opaque.)

Step 4

Transfer the fish to plates, leaving the excess butter in the pan. Cover fish to keep warm, or set fish in a 200ºF oven.Reduce heat to medium-low.  Add the remaining butter to the pan. The butter will begin to foam, and then the foam will begin to subside.Watch for brown specks to appear in the butter and for the butter to start smelling nutty. As soon as it begins to become golden (about 1 minute), add the lemon juice, stir, and then remove from heat.

Step 5

Pour the butter sauce into a small bowl and mix with the honey and cayenne.

Step 6

Brush the butter sauce over the fish. You'll see that the sablefish is incredibly soft and the flakes will be pulling apart, so the sauce will soak down into the fish.Serve the fish right away along with any extra sauce.