Pilih potongan (steak) atau lembaran (fillet) daging tuna segar atau beku. Buat campuran rempah-rempah untuk memasak ikan tuna. Panaskan wajan datar atau alat untuk membakar. Lapisi tuna dengan campuran rempah-rempah yang telah Anda buat. Bakar tuna pada kedua sisinya.

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Ahi tuna is sold in form of large steaks or fillets that can be cooked in a similar fashion to beef steaks. Look for deep red tuna steaks with firm flesh. Avoid steaks that have a rainbow sheen or look dry, also avoid buying fish that looks mottled or pale in color.  Buy a six-ounce steak per serving you need. If you're using frozen tuna steak, thaw it completely and put in the refrigerator before using. Fresh tuna is in season from late spring to early fall. If you're choosing fresh tuna, it's best to get it while it's in season. Frozen tuna is available all year round. Ahi or yellowfin tuna from the United States or Canada is the best choice, since it has relatively low levels of mercury and is not in danger of being overfished. Bluefin tuna should be avoided, as the mercury levels are higher and it is being over-fished across the world. Seared tuna is frequently coated with spices that complement the tuna's meaty flavour. You can use a steak rub or any other type of spice mix that includes ingredients like garlic powder, pepper and dried herbs. Try making your own spice mix by combining the following ingredients in a bowl (makes enough to coat one six-ounce steak):  1/2 teaspoon salt 1/4 teaspoon black pepper 1/4 teaspoon red pepper flakes 1/4 teaspoon garlic powder 1/4 teaspoon dried basil 1/4 teaspoon dried oregano Tuna steaks and fillets are easy to sear on either a grill or stove top. The key is to fully heat the cooking implement you're using before adding the tuna. This will ensure that the tuna cooks evenly and attains a good crunchy sear.  If you're using the stove top, heat a cast iron skillet or other heavy skillet over medium high heat. Add a tablespoon of peanut oil or canola oil and heat it until the oil just begins to smoke.  If you're using a grill, light the charcoal at least half an hour before you plan to cook the tuna. that way it will have plenty of time to get nice and hot before you add the tuna. Each six-ounce steak or fillet will need approximately one to two tablespoons of...