Seared Tuna Lettuce Cups with Wasabi Aioli Recipe

These Seared Tuna Lettuce Cups with Wasabi Aioli are a perfect summer dish for poolside meals or light dinners. They require minimal cooking, are bright and refreshing, and deliver bold flavor without feeling heavy. The combination of lightly seared sesame-crusted tuna, crisp vegetables, creamy avocado, and a subtly spicy wasabi aioli makes these lettuce cups both elegant and effortless.

If you’re wary of straight wasabi, this aioli version tones it down with mayo and lime so the heat is gentle and bright rather than overpowering. Use sushi- or sashimi-grade tuna for best texture when searing quickly; the center should remain tender and slightly rare unless you prefer it more cooked. These cups come together fast, making them ideal for warm-weather entertaining or a quick weeknight treat.

The tacos are built on soft butter lettuce leaves for a delicate, edible vessel that highlights the filling. Crisp julienned carrots and cucumbers add crunch, while avocado brings silkiness. A light drizzle of wasabi aioli ties the components together with a touch of acidity and heat. These lettuce cups are versatile—swap in other greens, add pickled ginger or a sprinkle of scallions, or serve alongside steamed rice for a more substantial plate.

Looking for more tuna recipes? Try these ideas

Pounded Tuna Carpaccio — Seared tuna thinly sliced and dressed simply with citrus and olive oil.

Seared Tuna and Soba Noodle Stir Fry Bowls — A heartier bowl option with noodles and vegetables.

Seared Tuna Salad with Pineapple-Sesame Dressing — Fresh greens and a sweet-savory dressing for warm nights.

Seared Tuna Lettuce Cups with Wasabi Aioli

Prep: 15 mins • Cook: 5 mins • Servings: 4

Ingredients

For the Wasabi Aioli:

1/4 cup mayo (homemade or store-bought)
1 tsp wasabi powder
1 tsp hot water
2 cloves garlic, minced
1 tbsp lime juice
1/4 tsp kosher salt

For the Tuna:

2 tuna steaks (6 oz each), sushi-grade recommended
1 tsp kosher salt
1/2 tsp white sesame seeds
1/2 tsp black sesame seeds
2 tbsp avocado oil (or other high-heat oil)

For the Lettuce Cups:

8 butter lettuce leaves
1/2 avocado, thinly sliced
1/2 cup carrots, julienned
1/2 cup cucumber, julienned
Cilantro for garnish

Instructions

Wasabi Aioli

In a small bowl, combine the wasabi powder and hot water. Allow it to sit for about 5 minutes so the flavors develop.
Mix the hydrated wasabi with the mayo, minced garlic, lime juice, and kosher salt. Taste and adjust seasoning. Refrigerate until ready to serve.

Seared Tuna

Pat the tuna steaks dry and season evenly with kosher salt. Press the white and black sesame seeds onto the surfaces of the tuna so they adhere.
Heat a nonstick or well-seasoned skillet over high heat and add the avocado oil. Heat until hot but not smoking.
Sear the tuna steaks 30 seconds to 1 minute per side depending on thickness and desired doneness. For a rare center, aim for about 30–45 seconds per side; for medium-rare, cook a bit longer. Remove from heat and let rest for a minute, then slice thinly against the grain.

Assemble the Lettuce Cups

Arrange butter lettuce leaves on a platter. Layer with a few slices of avocado, a small handful of julienned carrots and cucumber.
Top each leaf with sliced seared tuna. Drizzle with the wasabi aioli and garnish with cilantro. Serve immediately.

Serving Tips, Variations, and Storage

These lettuce cups are best served fresh. If you need to prepare ahead, make the wasabi aioli and prep the vegetables in advance. Store the tuna separately and sear just before serving so it stays warm and tender. Leftover seared tuna can be refrigerated and enjoyed within 24 hours, but texture and flavor are best the day it’s cooked.

Substitutions: Swap mayonnaise for Greek yogurt for a lighter aioli, or use low-sodium soy sauce and a touch of honey for a different dressing profile. If you prefer cooked tuna through and through, increase the sear time, but take care not to dry it out.

Additions: Pickled ginger, thinly sliced scallions, toasted sesame oil drizzle, or a sprinkle of furikake all pair nicely. For a heartier option, serve the tuna and toppings over steamed rice or in warm tortillas instead of lettuce.

Nutrition information is an estimate and will vary based on ingredients and portion sizes.