Z’s all time favorite thing to order when we go to “our” restaurant is seared Ahi over wasabi mashed potatoes. He’s mentioned a couple of times that it’s something we should try on the grill and up until now I’ve been a little … well … nervous. A chunk of sushi grade Ahi tuna is not cheap and while I’m pretty confident in my cooking and grilling skills, there’s something about this cook that for some reason intimidates me.
A month or so ago for date night, I decided it was time to take the plunge. If I screwed it up and overcooked it, we’d just have very expensive tuna salad!
I bought 2/3 lb of sushi grade ahi tuna at Whole Foods and kept it wrapped in the fridge overnight. Mid afternoon I mixed up some soy sauce, a little mayo, some brown sugar, and a heaping spoonful of wasabi powder and let the tuna sit in it in the fridge in a zipper sealed quart bag. I flipped it a couple of times over the course of the afternoon.
As part of the treat, I also roasted a few oysters as an appetizer (I’ll post that recipe later). When the oysters came off the grill, I removed the top grate, and put the cast iron griddle (with a very thin coat of olive oil) on the lowest grate to preheat at about 525°. I let the griddle get absolutely smoking hot and then put the tuna on. The white-ish color around the edges is the mayo/soy/wasabi mixture. And you can see the smoke coming off the griddle in the picture below!
I cooked it for a total of 30 seconds per “side”, meaning, I cooked not only the large flat sides, but the 3 “edges” as sides as well. The total time was 2 min and 30 seconds overall. When it came off the grill, I immediately put it in the freezer to stop it cooking and firm it up a little bit. I kept it there for maybe 3-4 mins while I mashed the potatoes and then took it out to slice.
It had a lovely browned color on the outside, but the real nervous-making part was what the inside would look like. I didn’t need to worry – it was perfect!
I served it with whipped potatoes mixed with cream and more wasabi powder, and lightly grilled asparagus.
It was fun to do this on the grill, but it could be done inside quite easily. I’d use my cast iron skillet on the stovetop and heat it up until it’s nearly smoking hot. Then the same 30 second sear on each side/edge of the tuna to get the rare center.
Here’s the recipe for the marinade for the tuna. Adjust the amount of wasabi powder to your taste; the amount here gives a nice flavor, but isn’t overbearing.
Seared Tuna Marinade
- 1/4 cup mayonnaise
- 2 tbsp soy sauce
- 1 tbsp brown sugar
- 1 tbsp wasabi powder
Dissolve the brown sugar in the soy sauce and then mix with the rest of the ingredients. Baste the tuna with the mixture and let it sit for at least a couple of hours before grilling. (I put mine in a quart sized Zip-lock bag and just flipped it a couple of times to coat the fish.)