Items you’ll need for killing, cleaning and transporting your fish include a mallet, sharp fillet knife, hook remover, fillet knife, serrated knife, cutting board, at least two buckets (for rinsing and discarding waste), cooler and ice.
A freshly caught steelhead or salmon should be killed immediately and cleaned as soon as possible. The most effective way to kill a salmon or steelhead is to hold it in one hand and strike it on the head behind the eyes with a mallet. Remove the hook by grasping it with your fingers or a pair of long-nosed pliers and backing it out. You can also use a special tool designed to remove hooks, available at sporting goods stores.
To prevent blood from spoiling the tissue, make several cuts in the gills (located under the gill flap below the eyes) with a knife and place the fish in a cold bucket of water. This allows the blood to flow out of the fish. Immediately clean the fish or place it on ice in a cooler.
When cleaning your fish:
- Angle the knife to cut away from yourself
- Take your time
- Remember the fish's mouth, gills, and bones can be sharp.
- Place the fish on the cutting board, belly up and head away from you. Locate the anus on the lower belly of the fish (small, round vent). Insert the fillet knife a fraction of an inch directly above the hole and gently cut upward along the belly to the throat. Don’t cut into the internal organs.
- Turn the fish on its side to cut off the head. Start cutting behind the head below the gill flap and pectoral fin. Cut down until you hit the backbone. Take care not to cut any internal organs. The meat on this side of the fish should now no longer be attached to the head.
- Turn your fish over and make a similar cut in the opposite side until you hit the backbone.
- Place your fish in whatever position is most comfortable for you and cut through the backbone to detach the head. You may need a sharper, or serrated knife.
- Pull out the guts of the fish. Discard the head and guts in a waste bucket.
- Remove the kidney — the long, dark red organ running along the top of the cavity underneath the backbone by cutting through it along its length. Then scrape it out with a spoon or your knife.
- Cut off the tail and discard in the bucket.
- Wash the fish thoroughly in cold water and place in cooler with ice.
Your cleaned salmon can be cut either into fillets or steaks, as detailed below:
- Lay the fish on its side and start a cut where the head was removed, just above the backbone.
- Using a sawing motion, cut along the backbone towards the tail. You may need to hold up the meat at the bottom of the cavity to keep it from getting sliced by the knife.
- Keep cutting until you reach the end. You now have one large fillet.
- Turn the fish over and begin cutting the other side just above the backbone.
- Using the same sawing motion, cut along the backbone towards the tail, keeping the meat up out of the way of the knife. You now have two large fillets. The only meat not recovered is a small layer along the backbone.
- Now you need to remove the ribs that are attached to the fillets. Begin by inserting the point of your knife into the meat at the first rib's mid-point, just beneath the rib, located toward the top of the fish. The meat and membrane between the ribs is semi-opaque so you should be able to see the knife blade through the meat. If you cannot see the blade then you've inserted the knife too deeply.
- With a slow, gentle sawing motion, carefully cut towards the bottom of the fillet while keeping the sharp part of the blade angled slightly upwards to avoid getting too deeply into the meat. Your knife should be cutting right along the ribs.
- If cut properly, you should have a small flap with the ribs, membrane, and a very minimal amount of meat. Using this technique, slowly work your way towards the thicker part of the fillet and towards the tail portion. You should end up with a long flap attached lengthwise to your fillet. This piece can be easily cut off.
A good photo tutorial on how to fillet a salmon may be seen on the Northwest Fly Fisherman website.
Larger fish such as salmon and steelhead can be cut into steaks. After the fish is cleaned, chill it to make it easier to cut. Place the fish on its belly. Starting at the tail, cut across the backbone, making each steak approximately 1-inch thick. After making steaks, trim away belly fat and bones, but don’t cut out the backbone.
Cooking time is fairly short when cooking whole fish or fillets to keep the flavors simple. Fish are cooked when the flesh flakes off easily with a fork.
In general, the cooking time for fish is 10 minutes for every inch of thickness—whether you bake, poach, broil, or grill. To test for doneness, slip the point of a sharp knife into the thickest part of the fish and pull aside. If flakes begin to separate, the fish is probably done. Remove fish from heat and let it stand 3 to 4 minutes to finish cooking.
Rinse fish and pat dry with a paper towel. Whole fish may be stuffed with rice and vegetables. Place whole, boned fish in a baking pan. Brush with butter and oil and season with salt and pepper, or cover with a piquant sauce. Bake in a preheated oven at 400°F (200°C) until a knife slice in the thickest part reveals the flesh to be opaque but still moist.
Place whole small fish or fillets on perforated aluminum foil over a greased grill, 4 to 6 inches (10 to 15cm) above prepared coals or fire. Baste with butter, oil, or marinade, and close hood of grill. Cook until opaque and moist on the inside, 6 to 8 minutes for fish less than 1 inch (2.5cm) thick; 10 to 15 minutes for fish larger than 1-inch (2.5cm) thick.
Rinse whole fish, fillets, or boned and butterflied trout, and pat dry with a paper towel. Place fish on a rack above a baking dish. Preheat broiler and adjust oven rack so fish is 3 to 4 inches (7.6 to 10cm) from the element. Brush with butter or oil and season with salt and pepper. Broil, turning once, until fish is opaque but still moist in the center, 3 to 10 minutes, depending on size of the fish.
Rinse fillets, and pat dry with a paper towel. Dredge in flour and seasonings if desired. Shake off any excess flour. Heat frying pan until hot, then add butter or oil. Put in fillets and cook, turning once, until fish is opaque but still moist in the center, 2 to 10 minutes, depending upon size of the fish.
Bring poaching liquid, consisting of water, broth, and herbs and spices, to a simmer. Slip fish in, then cover pan and keep liquid at a simmer for about 8 minutes per inch (about 2.5cm) of thickness.
Place fish on a greased perforated rack over 1 to 2 inches (about 2.5 to 5cm) of rapidly boiling water. Cover with a tight-fitting lid and keep water at a constant boil through cooking time, 8 to 10 minutes per inch (about 2.5cm) thickness of fish.