A sesame-crusted ahi tuna steak with a beautifully golden exterior and a cool, ruby-red center. It looks and tastes like a restaurant-quality meal, but comes together at home in less than 20 minutes.
Seared ahi tuna is one of my favorite things to order at a restaurant. The contrast is what makes it so good, a warm, nutty sesame crust surrounding incredibly tender, almost buttery tuna.
It can seem like an intimidating dish to recreate at home, especially when the center is meant to remain rare, but ahi tuna is actually one of the simplest proteins to cook. The secret is not a complicated technique. It is starting with high-quality tuna, getting the pan piping hot, and knowing exactly what to look for while it sears.
This is the kind of meal I make when I want something fresh and restaurant-quality without leaving my apartment. I serve the sliced tuna with rice, cucumber, and avocado for a simple, complete meal, but it is just as delicious on its own.
Why You’ll Love Seared Ahi Tuna Steak
- Restaurant-quality at home: The sesame crust, ruby-red center, and clean slices make this feel like something you would order while dining out.
- Incredibly quick: Once the tuna has marinated, it needs only about 90 seconds per side in the pan.
- Simple visual doneness cues: Instead of relying exclusively on the clock, you can watch the cooked band form along the sides of the steak.
- Fresh but satisfying: Serve it with rice, cucumber, and avocado for a complete meal that feels light without leaving you hungry.
Ingredients
- Ahi tuna steak: Choose a thick, evenly cut piece of high-quality tuna intended to be served rare or raw.
- Soy sauce: Seasons the tuna and creates the savory base of the quick marinade.
- Sesame oil: Adds a concentrated toasted, nutty flavor, so only a small amount is needed.
- Fresh ginger: Brings brightness and a gentle warmth that balances the richness of the tuna.
- Black and white sesame seeds: Create a crisp, dramatic crust with plenty of toasted flavor.
- Brown sugar: A small amount encourages caramelization and balances the salty soy sauce.
- Salt and black pepper: Season both the marinade and sesame coating.
- Olive oil: Helps the tuna sear quickly and evenly in the hot pan.
How to Make Seared Ahi Tuna Steak
- Choose the tuna. Look for a thick, evenly shaped ahi tuna steak with a rich, vibrant color and no dull, brown, or gray edges. Ask your fishmonger for tuna that is suitable for serving rare.
- Make the marinade. Combine the soy sauce, sesame oil, grated ginger, salt, and black pepper in a shallow dish. Add the tuna and turn it several times to coat every side.
- Marinate briefly. Allow the tuna to sit in the marinade for about 10 minutes. Keep this step short, since an extended marinade can begin to change the delicate texture of the fish.
- Prepare the sesame crust. Combine the black sesame seeds, white sesame seeds, brown sugar, salt, and pepper on a plate or in a shallow dish.
- Coat the tuna. Remove the steak from the marinade and allow the excess liquid to drip away. Press it firmly into the sesame mixture, turning until the top, bottom, and edges are completely covered.
- Heat the pan. Place a heavy skillet over medium-high to high heat. Allow it to become piping hot before adding the oil. The hot pan is what creates a proper crust without overcooking the center.
- Sear the first side. Gently lower the tuna into the pan, laying it away from you to avoid splattering. Cook without moving it for approximately 60 to 90 seconds.
- Flip and finish. Turn the tuna and sear the second side for another 60 to 90 seconds. Watch the sides of the steak rather than relying only on the clock. The tuna is evenly seared when the pale cooked bands are approximately the same width on both sides.
- Rest and slice. Transfer the tuna to a cutting board and let it rest for 1 to 2 minutes. Slice it against the grain using a sharp knife, cleaning the blade between cuts when necessary.
- Serve immediately. Enjoy the tuna as is, or serve it with rice, sliced cucumber, and avocado for a complete meal.
Tips and Tricks
- Start with a thick steak. Ahi tuna that is at least 1 inch thick is much easier to sear without accidentally cooking the center through.
- Do not marinate it for too long. Ten minutes is enough time to season the exterior without compromising the texture.
- Remove excess marinade. A dripping-wet tuna steak will steam in the pan and make it harder for the sesame coating to become crisp.
- Preheat the pan properly. The tuna should begin sizzling the moment it touches the surface. A lukewarm pan will overcook the fish before a crust develops.
My Pro Tip
Use the sides as your guide
Watching the cooked bands form gives you more control than depending on an exact cooking time, especially since tuna steaks vary in thickness.
- Use a very sharp knife. A dull knife can pull off the sesame crust and compress the tender tuna as you slice.
Substitutions
- Tamari: Use in place of soy sauce for a similar savory flavor.
- Neutral high-heat oil: Avocado, grapeseed, or another neutral oil can replace the olive oil for searing.
- One type of sesame seed: All white or all black sesame seeds will work if you do not have both.
- Honey: A small amount can replace the brown sugar, although the sesame mixture may be slightly stickier.
Leftovers
Seared ahi tuna is at its best immediately after cooking, while the exterior is warm and the center is tender.
Store leftovers in an airtight container in the refrigerator for up to one day. I prefer eating leftover tuna cold over rice, in a salad, or as part of a bowl. Reheating it will continue cooking the center and change its texture, so I would avoid putting it back into a hot pan or microwave.
FAQ
“Sushi-grade” is a term commonly used by sellers to indicate that the fish is intended to be eaten raw or undercooked, but it is not a standardized federal grade. Purchase tuna from a trusted seafood market and clearly explain that you plan to serve it rare.
The FDA notes that thoroughly cooking seafood is the safest option. Anyone who is pregnant, immunocompromised, very young, older, or otherwise at greater risk for foodborne illness should avoid raw or undercooked seafood.
The pan should be thoroughly preheated and piping hot before the oil and tuna are added. You should hear an immediate, strong sizzle when the steak touches the surface.
Look at the side of the tuna. Once a narrow pale band has formed along the bottom, usually after 60 to 90 seconds, flip the steak. Cook the second side until the bands appear even.
Yes, although the finished texture will be firmer and less buttery. Reduce the heat slightly after searing the exterior, then continue cooking until it reaches your preferred doneness. Fully cooking seafood is the safest preparation from a food-safety perspective.
Sesame-Crusted Seared Ahi Tuna Steak
Ingredients
- 1 large ahi tuna steak, approximately 8 ounces and at least 1 inch thick
- 1 tablespoon soy sauce
- ½ teaspoon toasted sesame oil
- 1 teaspoon freshly grated ginger
- ¼ teaspoon kosher salt, divided
- ¼ teaspoon freshly ground black pepper, divided
- 1½ tablespoons black sesame seeds
- 1½ tablespoons white sesame seeds
- 1 teaspoon brown sugar
- 1 tsp olive oil
Instructions
- Combine the soy sauce, sesame oil, ginger, half of the salt, and half of the black pepper in a shallow dish.
- Add the tuna steak and turn to coat it completely. Allow it to marinate for 10 minutes.
- Combine the black sesame seeds, white sesame seeds, brown sugar, remaining salt, and remaining pepper on a plate.
- Remove the tuna from the marinade and let the excess liquid drip away. Press the steak into the sesame mixture, coating the top, bottom, and sides.
- Heat a heavy skillet over medium-high to high heat until piping hot. Add the olive oil and swirl to coat the pan.
- Gently place the tuna in the pan and sear without moving it for 60 to 90 seconds.
- Flip and cook the second side for another 60 to 90 seconds, watching for evenly sized cooked bands along both sides of the tuna.
- Transfer the tuna to a cutting board and rest for 1 to 2 minutes.
- Slice against the grain with a sharp knife. Serve immediately, either on its own or with rice, cucumber, and avocado.
