Earlier this year, I was out with friends for dinner at Pascual, a fun restaurant on Capitol Hill in Washington, D.C., run by chefs Isabel Coss and Matt Conroy. (They are also the team behind Georgetown’s Lutèce.) My friend was put in charge of ordering for our table of four, so when the waiter returned with our drinks, he rattled off a list of plates we’d share.
“And the tuna tostada?” he asked the group. “We want the tuna tostada, too, right?”
Of course we did. Seemingly moments later, it arrived on an eggshell-white stoneware plate: a blue corn tostada spread with a thin layer of avocado, topped with fat slices of precisely cut tuna, plus bits of citrus, onions and herbs. It took us no time to finish, so we ordered another.
Looking around the dining room, my friend pointed out that every table within view had also ordered the tostada. It’s a straightforward dish, found along the coast in Mexico, but also in restaurants in Mexico’s central cities. Why, I wondered, hadn’t I made fresh tuna tostadas at home?
I decided to talk to Coss about her approach. “We almost always have it on the menu if tuna is in season,” she told me. “It’s such a classic Mexican dish. But it translates so well,” she said, noting that people who aren’t as familiar with Mexican food are just as likely to order it as people who have been eating Mexican food their whole lives.
“We even put it on the menu at Lutèce, because we missed cooking Mexican food,” Coss said with a little laugh. “But [at Pascual], it changes here and there, depending on the tuna we get, yellowfin or bluefin. I like it with a salsa macha, with a crunch, and avocado. I love fat on fat. Right now we have it with a pistachio salsa macha, tomatoes and tuna. It goes so well.”
How hard would it be to re-create this restaurant standard at home? My local grocery store had sushi-grade tuna steaks in the freezer section, so I grabbed them, along with a package of tostadas, a few avocados, limes, a bag of tangerines, a serrano chile and a bunch of cilantro.
When I got home, I put a couple of the vacuum-packed tuna steaks in a bowl of cold water and assessed the avocados. I remembered that a tuna tostada I’d had at Lutèce tasted of miso and mustard, so I mashed the avocado with mild shiro miso and punchy Dijon. This tasted great on its own, but it needed some acidity. Lime juice made it pop. At this point, the tuna was partially defrosted - an ideal state for slicing it thinly with a sharp knife.
