Confit Tuna Salad Sandwich
jump toRECIPE
This confit tuna sandwich transforms fresh ahi tuna into a rich, flavorful homemade tuna salad by slowly poaching it in olive oil with shallots and rosemary until tender and buttery. Combined with creamy mayonnaise, tangy pickled onions, roasted red peppers, crisp cucumber, avocado, and sprouts on toasted sourdough, this sandwich is bright, layered, and deeply satisfying. Inspired by gourmet deli-style sandwiches, it offers a more refined alternative to traditional tuna salad while still feeling approachable enough for lunch or casual entertaining.
The contrast of the confit shallots in the tuna salad with the pickled onions and fire-roasted peppers, avocado, cucumber and sprouts makes for an amazing summer sandwich. Score extra points by making homemade sourdough bread. Looking for more fresh sandwich recipes? Try my bacon turkey garden sandwich or this Italian sub sandwich next!
Why You’ll Love This Recipe
- Elevated yet approachable – A gourmet spin on tuna salad that feels special without being overly complicated.
- Packed with texture – Creamy tuna, crunchy cucumber, tangy onions, and crisp sprouts create balance in every bite.
- Great for make-ahead lunches – The confit tuna salad can be prepared in advance for easy assembly later.
What Inspired This Sandwich?
This recipe is inspired by the tuna conserva sandwich from Gjusta in Venice, California. The rustic open-kitchen shop with exposed beams and a long thick marble counter serves everything from sandwiches to pizzas and bread all using house-made ingredients. I appreciate a place that makes most things from scratch. It adds a unique and special touch, plus it’s just impressive.
What Is Confit?
While confit generally refers to something being cooked in its own oil, the term also applies to the method used here. While it can be served gently flaked apart and added to sandwiches or niçoise salad as is, in this recipe the cooked tuna is broken up and shredded. I take the tuna salad recipe a step further with mayonnaise and the confit shallots cooked with the fish.
Pro Tip
Use the leftover olive oil from the tuna confit as a flavorful base for vinaigrettes, roasted vegetables, or dipping bread—it’s infused with aromatics and adds extra value to the recipe.
Key Ingredients in This Recipe
- Tuna – Rather than quickly searing tuna or serving it raw, I slowly poach this tuna in olive oil. While it takes a bit of time, I prefer to make this confit tuna rather than using canned tuna since I have much more control over the seasoning, flavor and how it’s cooked.
- Shallots – Shallots have a mild and slightly sweet flavor. If needed, substitute sliced yellow onion for the shallot in this recipe. The general rule of thumb is 3 medium shallots equal 1 medium onion.
- Rosemary – I use fresh sprigs of rosemary in the confit tuna to add aromatics and a subtle herby flavor. Swap with another aromatic herb like thyme if needed.
- Mayonnaise – Mayo acts as a binder, holding the shredded confit tuna salad together and
- Olive oil – Extra-virgin olive oil is unrefined and made from pure, cold-pressed olives, giving it more of a true olive taste. I prefer to use it in this recipe rather than regular olive oil. Enough oil is needed to cover the fish as it cooks.
- Sprouts – Alfalfa sprouts are very young plants, harvested just after they germinate and add a mild, slightly nutty flavor and are mineral rich.
A full ingredient list with exact amounts can be found in the recipe card below.
Swaps and Substitutions
- Ahi tuna: Substitute with oil-packed jarred tuna for a quicker shortcut.
- Sourdough bread: Swap with ciabatta, baguette, or multigrain bread.
- Roasted red peppers: Use jarred fire-roasted peppers for convenience.
- Pickled onions: Substitute with capers or thinly sliced fresh red onion.
- Sprouts: Swap with arugula, butter lettuce, or microgreens.
- Rosemary: Use thyme or bay leaf for a different aromatic profile.
How to Make This Confit Tuna Salad Sandwich (Step-by-Step)
- Season tuna. Heat oven to 275ºF (140ºC). Season the tuna on both sides with salt and pepper and let sit for 20 minutes.
- Slowly bake the tuna. Add to an oven safe baking dish or Dutch oven and cover with the olive oil, using more if needed so the fish is just covered. Add the shallots and rosemary then cover and bake until the fish is tender and just cooked through, about 30 minutes.
- Make the fish salad. Let cool to the touch, about 15 minutes and discard the rosemary. Add the fish and shallots to a large mixing bowl and save the oil for another use. Add the mayonnaise and vinegar, using a fork to mash up the tuna. Season with salt and pepper to taste then set aside until ready to use. The tuna mixture can be made a day ahead of time then covered and refrigerated until ready to use.
- Roast red pepper. Char the red pepper over gas flame or in broiler until blackened on all sides. Enclose in a paper bag for 10 minutes.
- Slice peppers. After roasting the pepper, carefully peel off the charred skin. Slice the top part off the pepper (about the top 1/2″) discarding the stem and seeds. Cut the red pepper into strips and set aside.
- Assemble sandwich. Toast the sourdough bread then top 2 of the slices with tuna salad, avocado slices, cucumber slices, roasted red pepper, pickled onions and sprouts.
- Serve. Close both sandwiches and carefully slice in half with a bread knife. Serve immediately or wrap in parchment paper and refrigerate until ready to serve.
How to Serve a Confit Tuna Salad Sandwich
- As a gourmet lunch: Serve chilled or room temperature on toasted sourdough.
- With sides: Pair with kettle chips, potato salad, or a simple arugula salad.
- For entertaining: Slice into smaller sandwiches or tea sandwiches for gatherings.
- Picnic-style: Wrap tightly in parchment paper for easy transport.
How to Store a Confit Tuna Salad Sandwich
- Refrigerator: Store the tuna salad separately in an airtight container for up to 2 days.
- Bread: Toast fresh before assembling to prevent sogginess.
- Assembly: Assemble just before serving for the best texture.
- Olive oil: Strain and refrigerate leftover confit oil for future cooking use.
FAQ – Frequently Asked Questions
Confit tuna is freshly poached in oil at low heat, resulting in a more tender, rich, and flavorful texture than traditional canned tuna.
Yes, the tuna salad can be made up to 2 days ahead, but the sandwich is best assembled just before serving.
Sourdough, ciabatta, or crusty artisan bread work best because they hold up well to the rich filling.
Confit tuna is typically cooled, then served chilled or at room temperature in sandwiches or salads.
Confit tuna sandwich can offer fresher ingredients and less processed flavor, though richness depends on the olive oil and mayonnaise used.
Other Recipes to Try
If you loved this elevated confit tuna fish sandwich, check out some of my other favorite sandwich varieties next:
Thanks for cooking with me! If you made this recipe, leave a 🌟 rating and share your thoughts or tips below. I’d love to hear from you!
Confit Tuna Salad Sandwich
Rate this Recipe
Ingredients:
For the confit tuna:
- ¾ pound ahi tuna
- Kosher salt, as needed
- Freshly ground black pepper, as needed
- 2 cups extra-virgin olive oil, additional as needed
- 2 medium shallots, sliced
- 3 sprigs rosemary
- ⅓ cup mayonnaise
- 2 teaspoons white wine vinegar
For serving:
- 1 medium red bell pepper, (or substitute with a jar of fire-roasted red peppers, cut into strips)
- 4 slices sourdough bread
- 1 medium Haas avocado, peeled, pitted and sliced
- ½ cup thinly sliced cucumber
- ¼ cup pickled onions
- 1 cup sprouts
Instructions:
For the confit tuna:
- Heat oven to 275ºF (140ºC).
- Season the tuna on both sides with salt and pepper and let sit for 20 minutes.
- Add to an oven safe baking dish or Dutch oven and cover with the olive oil, using more if needed so the fish is just covered. Add the shallots and rosemary then cover and bake until the fish is tender and just cooked through, about 30 minutes.
- Let cool to the touch, about 15 minutes and discard the rosemary. Add the fish and shallots to a large mixing bowl and save the oil for another use. Add the mayonnaise and vinegar, using a fork to mash up the tuna. Season with salt and pepper then set aside until ready to use.
- The tuna mixture can be made a day ahead of time then covered and refrigerated until ready to use.
For serving:
- Char the red pepper over gas flame or in broiler until blackened on all sides. Enclose in a paper bag for 10 minutes.
- After roasting the pepper, carefully peel off the charred skin. Slice the top part off the pepper discarding the stem and seeds. Cut the red pepper into strips and set aside.
- Toast the sourdough bread then top 2 of the slices with tuna salad, avocado slices, cucumber slices, roasted red pepper, pickled onions and sprouts.
- Close both sandwiches and carefully slice in half with a bread knife. Serve immediately or wrap in parchment paper and refrigerate until ready to serve.
Notes:
Nutrition:
TAG ME ON INSTAGRAM TO BE FEATURED ON MY STORIES! @cookingwithcocktailrings
You will never buy or eat canned tuna again after making the confit tuna! The tuna comes out absolutely perfect. So moist and flavorful. I eat a lot of salads throughout the week and topped some of the leftover tuna with the salad and it made it just perfect. I also used the leftover tuna for my son’s tuna mac and he devoured it. Soooooo good Kylie! Love how versatile this recipe is.
I feel you on the canned tuna – it’s hard to go back!! Wow I still love tuna mac to this day and I will have to use that next time!
I especially like your swaps and substitutions section of suggestions of adding celery, swapping out vinegar for lemon, and trying herbs like parsley & chives (I think fennel also goes well here). Those seemingly small changes make a big difference in the taste of the sandwich. If I would do any tweak(s) myself, it would be to add a tapenade and remove or go light on the avocado, but for those that like the creaminess, I’d suggest to leave in the avocado. I agree that this is quite a versatile recipe. Thank you very much Kylie.