Tuna steaks are a popular and versatile cut of fish that you can prepare in many different ways with a wide variety of seasonings and marinades. Although tuna steaks are most often seared quickly on a hot grill or skillet, you can also get delicious results from cooking them in the oven. Know that tuna steaks are best cooked rare or medium-rare so that the inside remains pink, so opt for a hot and fast bake. This could be on a sheet pan – include some vegetables for a one-pan meal – or wrapped in a loose foil package with some aromatics.
If you are using frozen tuna steaks, thaw them in the refrigerator before proceeding with one of these two cooking methods.
Oven-Baked, Sheet-Pan Tuna Steaks
Cooking tuna steaks on a sheet pan in the oven couldn't be simpler, and it's a method that lends itself to one-pan meals with vegetables and fish all cooked together. Heat the oven to 450 degrees Fahrenheit and prepare the pan, tuna steaks and other ingredients while it heats up. You can use a baking dish or oven-proof skillet if you prefer and optionally cover the pan with foil for easier cleanup.
If you're going to marinate the tuna steaks, do so approximately 15 minutes before putting them in the oven; they don't need much longer than that. Otherwise, prepare the tuna steaks by brushing them with oil or melted butter and seasoning both sides with a little salt and pepper plus other seasonings of your choice. Lemon juice or slices, fresh or dried garlic and an Italian seasoning blend is a nice combination, as is fresh ginger and garlic plus a dash of soy sauce and drizzle of sesame oil.
Place the pan in the oven and bake the tuna steaks for four to six minutes per half-inch of thickness or until they're done to your liking when tested with a fork. For a one-pan meal, place the tuna on the pan alongside quick-cooking vegetables, such as asparagus, broccoli, zucchini and green beans. You can also start baking vegetables that need a longer cooking time, such as potatoes and carrots, before adding the tuna steaks. Pay attention to the cooking times so everything is done at the same time.
Oven-Baked Tuna Steak in Foil
Another method for baking tuna steaks in the oven is to wrap them in foil packages with seasonings and optionally some aromatics. Oven-baked tuna steak in foil uses a method known as en papillote, which combines steaming and baking to produce very tender fish. A dash of liquid, such as white wine, citrus juice, soy or teriyaki sauce, adds lots of flavor while steaming the fish, as do thinly sliced aromatics like onions, leeks, carrots and fennel. Also consider adding other suitable ingredients to the foil package, such as capers, olives, cherry tomatoes, thinly sliced mushrooms and spinach.
To make oven-baked tuna steak in foil, heat the oven to 400 degrees Fahrenheit and prepare two pieces of foil per tuna steak. Place a seasoned tuna steak in the center of the double layer of foil and add your choice of other ingredients on top of the fish. Bring two opposite edges of the foil together above the fish, fold them down tightly and then do the same with the other two sides of the foil to form a secure package. Place the package on a pan or dish and bake it in the oven for 15 to 20 minutes per inch of thickness.