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My easy tuna casserole recipe is the ultimate dump-and-bake dinner. Made with just a few simple ingredients, you can enjoy a perfectly cheesy tuna bake in under 20 minutes. It’s high in protein, low in carbs, and easy to meal prep too.
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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 not always easy to make canned tuna taste like something truly delicious (I mean, hello, tuna tartare, tuna carpaccio, and ahi tuna). However, I’ve nailed it with the right combination of ingredients. Now, most tuna casseroles call for noodles and cream of mushroom soup, but not my one! This is great if you are gluten-free, keto, or watching your carbs.
Tuna casserole recipe highlights
- 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’re worried about the potential fishy taste, don’t be — the cheese and mayo do a fabulous job of covering it up.
- Healthy: Canned tuna in springwater packs in tons of protein, very little fat, and much less sodium than tuna in brine. You get some extra vegetables and nutrients from the cauliflower, as well as healthy fats and more protein from the cheese.
If you want some of my other favorite ways to use canned tuna, try my tuna patties, tuna croquettes, and healthy tuna salad.
Key Ingredients
Scroll down to the recipe card below for the full list of ingredients. These are just a few notes about the main ones:
- 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. Use both to provide extra creaminess for this casserole. Don’t use one or the other, or you’ll be left with a super-rich casserole (all mayonnaise) or a super-stodgy one (all sour cream).
- Cauliflower. Adds some bulk and nutrients to the dish. This is entirely optional, and you can omit it if you like. If using cauliflower, please cook it beforehand (I recommend my air fryer cauliflower for a speedy option).
- 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.
How to make tuna casserole
This is an overview with step-by-step photos. Full ingredients & instructions are in the recipe card below.
Step 1- Flake the tuna and add it to a mixing bowl, along with the remaining ingredients. Mix until combined.
Step 2- 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.
★★★★★ REVIEW
“Once again, Arman’s recipe is killing it. I’ve done this recipe, the salmon patties, and the chili. All five stars in my opinion. It’s hard finding stuff that tastes good and that’s easy to make while doing keto.” – Crystal
My top tips for perfect tuna casserole
- Do not overbake. This dish requires a creamy and rich texture, so avoid overbaking. 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 tiny 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.
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.
- Storage: Place leftovers in an airtight container in the fridge, and it will be good for up to 4 days.
Nutrition
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. 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.
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!