Tunacado Sandwich (Simple & Flavor-Packed)

Name: Tunacado Sandwich
Prep time: 10 min
Total time: 10 min
Ingredients: 6 ounces chunk tuna (drained and flaked); 1 green onion (finely diced); 1 tablespoon drained capers (chopped); 1 tablespoon fresh dill (finely chopped); 1 tablespoon Dijon mustard; 2 tablespoons plain Greek yogurt; 1 tablespoon mayonnaise; 1 tablespoon lemon juice; Kosher salt and pepper (to taste); 4 large slices bread (toasted (or flatbread)); ¼ avocado (or ½, thinly sliced); 1 medium tomato (beef or Roma tomatoes, sliced); 1 tsp olive oil

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This Tunacado Sandwich is creamy, tangy, and fresh with layers of tuna, avocado, and tomato on toasted bread. Made in minutes, it’s perfect for lunch, easy to prep ahead, or enjoy as a light dinner. Keep it classic or try it with chickpeas for a veggie twist!

Two stacked halves of a tunacado sandwich on toasted bread, garnished with a lemon slice, fresh dill, and green onion.

The tunacado sandwich made its name at Joe & The Juice, and honestly, it deserves the spotlight. Creamy tuna mousse, buttery avocado, juicy tomato, and that little kiss of olive oil…it’s the kind of combo that feels fancy without trying too hard.

If you’re into creamy sandwiches that still feel fresh and satisfying, you’ll also enjoy my Avocado Egg Salad Sandwich, Chipotle Chicken Avocado Melt, and my Chickpea Avocado Sandwich (Vegan).

Recipe Overview

Skill Level

Beginner

Prep Time

10 mins

Cook Time

0 mins

Before You Get Started

A few helpful tips before you dive in:

Use ripe but not mushy avocado so it slices and layers nicely.
Toasting the bread makes all the difference – it holds up better to the creamy filling.
Mash the tuna until creamy, but leave a little texture for the best bite.
Taste as you go since mustard, yogurt, and capers all bring their own saltiness.
If using Tuna in oil, skip the olive oil.

Common Questions

Do I have to use capers?

No, you don’t have to. They give a tangy little punch, but if you’re not a fan, chopped green olives are a great stand-in.

What’s the best way to keep the sandwich from tasting bland?

If you make it as written, it won’t be bland – the dill, capers, mustard, and lemon already give it tons of flavor. But if you skip or swap something, just balance it out with extra herbs, an extra squeeze of lemon, or even a pinch of spice to keep it lively.

Can I make this dairy free?

Yes! Just use all mayo or swap the Greek yogurt for a plain, unsweetened dairy-free yogurt. It’ll still be creamy and delicious.

Can I mash the avocado with the tuna?

Yes. You actually can do that if you prefer.

Ingredients Needed

Below are the ingredients you’ll need to make the Tunacado Sandwich. The full quantities can be found in the recipe card further down the post.

ingredients to make a tuna and avocado sandwich.

Canned tuna: Use flaked or chunk tuna packed in water or olive oil, drained well. You can also use canned salmon or even mashed chickpeas for a vegetarian swap.
Green onion: Red onion, finely diced, works as a substitute if that’s what you have.
Capers: Briny and tangy, they really brighten the tuna. It can also be optional.
Fresh dill: Swap for parsley or chives if dill isn’t on hand.
Dijon mustard: Yellow mustard or spicy brown mustard will also work.
Plain Greek yogurt: Regular plain yogurt or a dairy-free yogurt can be used instead.
Mayonnaise: For that classic tuna salad texture. There are some healthier options out there, like avocado oil mayo by Chosen Foods. Or you can use more Greek yogurt if you prefer to skip it.
Lemon juice: Fresh is best, or lemon juice will work in a pinch.
Kosher salt and black pepper
Bread: Choose your favorite sandwich bread and toast it. Flatbread or sourdough are both great options.
Avocado: Thinly sliced and ripe but not mushy. Hummus can be used as a creamy alternative if you’re out of avocado.
Tomato: A medium beef tomato works well. Roma or heirloom tomatoes are also good choices.
Olive oil: Just a touch of extra virgin olive oil to finish. Any good-quality olive oil will do.

How to Make a Tunacado Sandwich

Here’s how to get perfect results every time:

process shot to make the tuna filling for a tuna sandwich.

1️⃣ Mix the Tuna Filling

In a small bowl, combine the tuna with green onion, capers, dill, Dijon mustard, Greek yogurt, mayonnaise, lemon juice, salt, and pepper.

✏️ Taste as you go, as different tuna brands vary in saltiness, so adjust seasoning to your liking.

2️⃣ Mash into a Spread

Mash with a fork until the tuna mousse comes together into a thick, spreadable paste.

✏️ Leaving just a little texture makes the sandwich more satisfying.

process shot for assembling the tuna sandwich.

3️⃣ Build the Sandwich Layers

Spread the tuna mixture on one slice of toasted bread. On the other slice, layer the avocado and tomato, then season with salt, pepper, and a drizzle of extra virgin olive oil.

✏️ Pat your tomato slices dry before layering so the bread stays crisp.

4️⃣ Close and Slice

Bring the two halves together, slice in half, and serve right away.

✏️ For the neatest cut, use a sharp serrated knife so the layers stay intact.

A hand holding a cut sandwich with avocado and tomato layers, placed on parchment over a wooden board.

Variations & Tips

→ Use flatbread instead of sliced bread for a wrap-style tuna avocado sandwich.

→ Add a slice of cheese like Swiss or provolone and melt it for a warm, café-style twist.

→ Make it spicier with a pinch of chili flakes or a drizzle of hot sauce in the tuna mixture.

→ For extra crunch, layer in thin cucumber slices or shredded lettuce with the avocado and tomato.

Storage Recommendations

Fridge: This sandwich is best enjoyed freshly made. You can prep the tuna filling ahead and store it in an airtight container in the fridge for up to 4 days, then add it with the avocado and tomato to the bread when you’re ready to eat.
Freezer: I don’t recommend freezing this one since the mayo and yogurt in the tuna filling don’t hold up well after thawing. It’s best made fresh or stored in the fridge for a few days.
Reheating: This sandwich is best enjoyed cold or at room temperature, but you can also warm it up. Pop it in a panini press, toastie maker, or even on a skillet if you’d like it toasted. Adding a slice of cheese before grilling makes it extra melty and café-style.