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This easy tuna casserole recipe is the ultimate dump-and-bake dinner. Made with only a few simple ingredients, you get a perfectly cheesy tuna bake in just 20 minutes.
When my family craves something hearty yet affordable, I love to whip up this cheesy tuna casserole. It features a creamy tuna mixture (with hidden veggies) topped with plenty of melted cheese. It’s accidentally low-carb, but no one would know.
Table of Contents
Why I love this recipe
- It takes canned tuna to the next level. It’s not always easy to make canned tuna taste like something truly delicious (I mean, hello tuna tartare, tuna carpaccio, and seared ahi tuna). However, it’s pretty much perfection when combined with cheese and mayonnaise and baked with more cheese.
- Easy and quick. I sometimes even prep it IN the dish so I only have one thing to clean up at the end.
- Perfect texture and flavor. The texture is thick and creamy, with morsels of melty cheese throughout. If you are worried about the potential fishy taste, don’t be —the cheese and mayo do a fabulous job of covering it up.
- Wholesome. This tuna bake has no noodles and no cream of mushroom soup. These are two typical ingredients in most tuna noodle casserole recipes, but not this one. Don’t fret, though—it’s every bit as hearty and creamy as you’d expect.
If you love cooking with canned tuna, try my tuna patties, tuna croquettes, and healthy tuna salad next.
Key Ingredients
- Tuna. I recommend using solid white albacore tuna in water for a light and flaky texture. Avoid tuna that is flavored or packed in oil, as it will make the casserole greasy.
- Mayonnaise and sour cream. These two condiments taste so much better when mixed together. Use both to provide extra creaminess for this casserole. Don’t use one or the other or else you’ll be left with a super-rich casserole (all mayo) or super-stodgy one (all sour cream).
- Cauliflower. Adds some bulk and nutrients to the dish. This is completely optional, and you can omit it if you like. If using cauliflower, please cook it beforehand (I recommend my air fryer cauliflower for something speedy).
- Onion. I like to use finely chopped green onions for a refreshing and mild onion flavor. Of course, diced white onion is fine.
- Mustard. Go with Dijon mustard for a tangy and slightly spicy flavor. It balances out the creaminess of the mayo and sour cream.
- Cheese. I use mozzarella cheese in the tuna mixture and gruyere to top the casserole. You can use any cheese that melts well, including cheddar or parmesan.
- Spices. Pepper and smoked paprika, used in the right amounts, don’t overshadow the mild flavor of canned tuna. I sometimes add garlic powder, too.
How to make tuna casserole
I’ve included step-by-step photos below to make this recipe easy to follow at home. For the full printable recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.
Step 1- Prep: Flake the tuna and add it to a mixing bowl, along with the remaining ingredients. Mix until combined.
Step 2- Assemble: Transfer the tuna mixture into the baking dish. Smooth out the edges.
Step 3-Add shredded cheese to cover the top.
Step 4- Bake for 15-20 minutes or until the cheese is melted and golden brown. Remove from the oven and serve warm.
Arman’s recipe tips
- Do not overbake. This dish requires a creamy and rich texture, so do not overbake. Once the cheese has nicely melted, it’s fine to remove it from the oven.
- Flake the tuna into larger chunks. If you flake it into very small pieces, the tuna mixture will turn into mush when you mix the canned fish with the rest of the ingredients.
- Grate the cheese by hand. I know it’s an extra step, but shredding the cheese by hand will yield a more gooey and perfectly melted topping.
Storage instructions
To store. Place leftovers in an airtight container in the refrigerator and it will be good for up to 4 days.
To freeze. Once the casserole has cooled, place portions of it in a shallow container and store it in the freezer for up to 6 months.
To reheat. The best way to reheat any casserole is in the oven, covered with tinfoil. You can also microwave small servings of it.
Frequently asked questions
The main reason why tuna casseroles turn out dry is that you have left them in the oven for too long. The tuna used for the casserole is already cooked, so once the cheese has melted, it’s ready to be enjoyed.
Yes, you can add noodles to this recipe. In fact, egg noodles are one of the main ingredients of the traditional version of this popular American casserole. Cook the noodles al dente before you add them to the rest of the ingredients. I actually prefer rotini pasta or elbow macaroni because they are smaller and hold the cheese and tuna mixture very well.
Yes! There are no ingredients that contain wheat or gluten.
Because this casserole is hearty and full of rich flavors, it’s best to keep the sides simple. I fine a fresh green salad or some steamed vegetables to tick the boxes.
More casserole recipes you’ll enjoy
- Squash casserole
- Philly cheesesteak casserole
- French onion chicken casserole
- Spaghetti squash casserole
Easy Tuna Casserole Recipe
Video
Ingredients
- 20 ounces canned tuna in springwater
- 1 cup mayonnaise
- 1/3 cup sour cream
- 1/2 teaspoon salt
- 1/2 teaspoon pepper
- 1/4 teaspoon smoked paprika
- 2 tablespoons Dijon mustard
- 1/2 cup green onions chopped
- 2 cups cauliflower cooked and chopped
- 1 cup mozzarella cheese
- 1 cup gruyere cheese
Instructions
- Preheat the oven to 180C/350F. Grease a large baking dish.
- In a mixing bowl, add the drained tuna and flake it with a fork. Add the mayonnaise, sour cream, salt, pepper, smoked paprika, green onions, and Dijon mustard. Mix until smooth. Add the cauliflower then fold through the mozzarella cheese.
- Transfer the mixture into the greased baking dish and top with gruyere cheese.
- Bake the tuna casserole for 15-20 minutes, or until the cheese is golden brown.
- Remove the casserole from the oven, let it sit for a minute, then serve.
Notes
- Add a crumb topping. Sprinkle the casserole with a breadcrumb and melted butter mixture for a golden and crispy crust that will contrast beautifully with the creamy tuna mixture. Other delicious options include crushed potato chips, ritz crackers, or panko bread crumbs.
- Use different vegetables. We prefer cauliflower for its mild flavor, but you can definitely amp up the casserole with other vegetables. Peas and corn always work well, as do some finely diced celery and carrots.
- Make it healthier. For a healthy tuna casserole, swap out the sour cream for Greek yogurt and use low-fat mayonnaise.
Nutrition
Originally updated September 2023, updated and republished February 2025
Once again Arman’s recipe is killing it. I’ve done this recipe, the salmon patties and the chili. All 5 stars in my opinion. It’s hard finding stuff that tastes good and that’s easy to make while doing keto.
I made this recipe last night with some substations. I was out of mozzarella so used cheddar cheese. Thought I had guvere cheese but it was fontana. I used frozen cauliflower florets thawed. Was concerned but the recipe was delicious. Thank you.
Delicious! Best tuna casserole ever! Common ingredients easily sourced in most areas. Uncommon taste and texture. Added the peas, sautéed mushrooms and topped with Old Bay. It’s a keeper recipe.
Love to hear that, Cork!
This is one of my favorites! Having it for dinner tonight 🙂
Dear Arman, I rarely comment on anything but as I’ve been making this recipe on a weekly basis for the past 6 months (I know, how obsessed can you be with a recipe? Ahaha) and as I’m so in love with it, I couldn’t not leave this comment! I’ve made this recipe in so many different ways, as a casserole, as a spread, as a dip, as a wrap filling with spinach and sun dried tomatoes, as pizza topping, with pasta, with rice, with noddles, with zoodles, with spiralized carrots, with the original ingredients, with the sub ingredients, etc. (You get the idea! 😅) Oh well, I guess we’re definitely in love with this. And the best part is that my ultra picky daughters (and husband!) absolutely love it too, so THANK YOU SO MUCH! 🩷 Love from Portugal! 🥰🙋🏻♀️
Iris, you are such a gem!!!!
Mayinnaise and sour cream go well together? Didnt know…
All ingredients that I like. Very interesting. Healthy good. Proteins.
Excellent!