This recipe is a bright, crunchy hand-held bite that has become my go-to for sunny lunches and easy entertaining. I first put these together on a lazy Saturday when I was craving something fresh after a week of heavy dinners. The combination of cool cucumber, creamy mashed avocado, soft sushi rice and warm, seasoned shrimp is unexpectedly satisfying: each bite gives a contrast of textures and a balance of sweet, tangy and mildly spicy flavors. It’s the kind of dish that feels special without requiring a long ingredient list or complicated techniques. What makes these boats truly memorable is how fast they come together and how well they travel to picnics and potlucks. I discovered the format while trying to use up leftover sushi rice and ripe avocados — the shrimp were simply a late addition to give some protein and color. Once I plated the first boat and tasted that salty, citrusy shrimp against the buttery avocado and crisp cucumber, it became a repeat request in our house. Kids and grown-ups alike love the hands-on nature, and I often double the batch because seconds disappear quickly.

Ingredients

• Cooked sushi rice — 1 cup: Use short-grain sushi rice for the slightly sticky texture that holds in the cucumber boats. If you use leftover rice, warm it briefly so it spreads easily. Brand note: Nishiki or Lundberg make reliable short-grain rice.
• Large cucumbers — 2: Choose firm English or Persian cucumbers for thin skin and fewer seeds. They create neat boats and are less watery than garden cucumbers.
• Shrimp — 24 medium, peeled and deveined: Fresh or frozen-and-thawed, about 3 ounces per 3-shrimp boat. Wild-caught or sustainably farmed options work; thawed shrimp should be patted dry before seasoning.
• Olive oil — 2 tablespoons: Light or extra-virgin will both work; oil helps the seasoning adhere and keeps shrimp juicy while searing.
• Seasoning blend: Garlic powder, onion powder, paprika, chili powder, dried oregano — about 3/4 teaspoon of each per the list — plus salt to taste for a warm, aromatic crust.
• Avocados — 3 medium: Ripe but still firm; mash until just smooth for body without becoming runny. Lime juice prevents browning and brightens flavor.
• Kewpie or regular mayonnaise — 1/4 cup: Kewpie gives a richer, slightly tangy finish thanks to rice vinegar; regular mayo works fine too.
• Sriracha — 2 teaspoons and honey — 1 teaspoon (optional): For a balanced spicy-sweet mayo. Adjust to taste.
• Sesame seeds — 1 tablespoon: Toast lightly in a dry pan for nutty flavor and visual contrast.

Instructions

Season and cook the shrimp: Toss 24 peeled, deveined shrimp with 2 tablespoons olive oil and 3/4 teaspoon each of garlic powder, onion powder, paprika, chili powder and dried oregano plus salt to taste. Heat a large skillet over medium-high heat until shimmering, add the shrimp in a single layer, and cook until opaque and pink, about 2 minutes per side for medium shrimp. Shrimp cook very quickly; remove as soon as they curl and are firm to avoid rubberiness. If using frozen shrimp, ensure they are fully thawed and patted dry so they sear rather than steam. Make the avocado mash: In a bowl, mash 3 ripe avocados with the juice of 1 lime and a pinch of salt. Leave some small chunks for texture; overly smooth avocado can become greasy when combined with mayo. Taste and adjust salt and lime — the mash should be bright and slightly tangy to cut the richness of the avocado. Whisk the spicy mayo: Combine 1/4 cup mayonnaise, 2 teaspoons Sriracha and 1 teaspoon honey (optional) in a small bowl. Whisk until smooth, then taste. Add more Sriracha if you prefer more heat or a touch more honey to tame spiciness. Transfer to a squeeze bottle or small bowl for easy drizzling. Prepare the cucumber boats: Wash and dry cucumbers. Slice lengthwise and then halve each half again to form quarters. Use a small spoon to scoop out seeds and some inner flesh to create hollow boats that hold rice and avocado without leaking. Pat interiors dry with paper towels if very wet. Assemble the bases: Spread about 1 tablespoon of the avocado mash into the base of each cucumber boat. Spoon roughly 2 tablespoons of cooked sushi rice over the avocado, pressing gently so the rice stays in place. The rice layer provides structure and a familiar sushi-like texture in each bite. Top and finish: Arrange three cooked shrimp on each filled boat. Drizzle spicy mayo over the shrimp and finish with a sprinkle of toasted sesame seeds. Serve immediately so cucumber retains its crunch and avocado does not discolor.

Storage Tips

Store avocado mash and spicy mayo in separate airtight containers in the refrigerator for up to 3 days; press a piece of plastic wrap directly on the surface of the avocado to minimize browning. Assembled boats are best eaten immediately, but if you must store them, keep the cucumber halves and fillings separate. Refrigerate the cucumber shells in a sealed container for up to 24 hours and assemble within a few hours of serving to preserve texture. Reheat cooked shrimp gently in a warm skillet for 1–2 minutes if you prefer them warm before assembly.

Ingredient Substitutions

If you don’t have sushi rice, use short-grain rice or even quinoa for a lighter, nuttier texture; reduce quantity to 3/4 cup cooked to avoid over-filling. Swap shrimp for cooked, flaked salmon or smoked tofu for a vegetarian-friendly alternative (note: tofu version is no longer pescatarian). If Kewpie mayo isn’t available, regular mayonnaise works; for a lighter version, use Greek yogurt mixed with a tablespoon of olive oil and a splash of rice vinegar, though flavor will be tangier and less rich.

Serving Suggestions

Serve these boats on a large platter with lemon or lime wedges for added brightness. They pair well with a simple green salad, pickled ginger and a cold glass of white wine or sparkling water with cucumber. Garnish with thinly sliced scallions, microgreens or a drizzle of sesame oil for an elevated finish. For a party, arrange boats on a long board and sprinkle extra toasted sesame seeds and a few nori strips for visual contrast.

Cultural Background

These boats combine elements inspired by Japanese rice and American finger-food presentation rather than a strict traditional dish. The use of sushi rice and sesame nods to Japanese influence, while avocado and spicy mayo reflect modern fusion trends popularized in coastal cafes. This mash-up is a good example of how fresh ingredients and simple techniques can create a dish that feels global yet approachable.

Seasonal Adaptations

In summer, use the ripest avocados and add diced mango for a tropical twist; in cooler months substitute microgreens and roasted sweet corn for extra warmth and texture. For a holiday party swap shrimp for small seared scallops and add finely chopped chives for a festive lift. Adjust the spice in the mayo to suit the season — more Sriracha in winter for a warming kick; lighter, citrus-forward mayo in summer.

Meal Prep Tips

Plan for assembly on the day of serving: make avocado mash and spicy mayo up to 4 hours ahead and keep chilled. Precook shrimp and keep them in a shallow container in the fridge; quickly reheat in a hot skillet for 1–2 minutes just before assembling. Portion rice into small containers so it warms evenly. Pack boats in shallow airtight containers for transport and drizzle mayo at the last minute to prevent sogginess.

These cucumber boats strike a lovely balance between ease and elegance; they are ideal for busy cooks who want something light, flavorful and visually appealing. Share them with friends, adapt them to your pantry, and make them your own — simple swaps keep the format fresh and exciting.