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Yes, you can actually pull together a delicious, nutritious, and easy dinner with just a few pantry staples! Skip a trip to the grocery store and use what’s already in your kitchen to serve your family this cozy 3-Ingredient Tuna Casserole at the end of a busy fall day!

A tuna casserole in a white dish with a serving spoon

Well, here we are…right smack in the middle of September! So long summer vacations, and hello back-to-school routines! I must admit — I’m enjoying every minute of the quieter house, cooler temps, and structured days. My boys do so much better with a predictable schedule (and so do I)!

While our summer was packed full of fun adventures, we’ve gladly slipped right back into the busy weeknight routine of homework, multiple sports practices, and simple family dinners! Although, honestly, we could do without the homework…

An overhead shot of a tuna casserole beside a box of horizon cheesy pasta

A Family Favorite Recipe

This 3-Ingredient Tuna Casserole recipe originally came from a reader named Sam, who was a member of the 5-Day Meal Planning Challenge that I hosted about a month ago. We were sharing some of our go-to weeknight meals in the Facebook group and Sam mentioned that this is one of her family’s favorites.

A close up of a tuna casserole in a white dish

I instantly knew that it would be a hit with my own crew of mac-and-cheese lovers, so I gave it a try the very next week. I had everything in my kitchen and I didn’t even need to run to the grocery store!

A close up of a tuna casserole topped with green onions

The tuna casserole was obviously a great success around our dinner table, so Sam said that I could share it with YOU as well! After all, when we’re knee-deep in the hustle of back-to-school season, we could all use a simple one dish comfort food meal to make our lives just a little bit easier!

A tuna casserole topped with green onion in a white dish

Sam’s original recipe calls for just 3 ingredients: Horizon Organic Cheddar Cheesy Deluxe Mac and Cheese, a bag of frozen peas, and a couple of cans of tuna. That’s it! You get carbs, protein, and veggies all in one dish — so you don’t even have to worry about the sides!

This is my boys’ #1 favorite mac and cheese on the market, which is why I recently stocked up when the boxes were on sale at my local grocery store (2 for $5).

Since Horizon’s mac and cheese is made with organic pasta and organic cheese, It’s an affordable dish that I can feel good about feeding my family. Plus, the delicious taste even encourages my boys to eat their seafood and veggies! Anything coated in that cheesy, creamy sauce is bound to be amazing!

How To Make This Tuna Casserole

The mac and cheese, tuna, and peas are combined in a large dish, covered with foil, and baked in the oven (just until the peas are heated through and the casserole “sets”).

Since my Great Aunt Bee always puts a buttery crumb topping on her tuna casserole, I decided to do the same! This step is totally optional (and it’s not part of Sam’s original 3-ingredient recipe), but I think it makes the dish just a little bit more special.

A crumb topping in a bowl for a tuna casserole

Melted Horizon Organic Butter and a bit of Panko bread crumbs add just the right touch on top!

A side shot of a tuna casserole in a white dish

I hope that you enjoy this simple, wholesome, and easy weeknight dinner — just in time for fall comfort food, busy back-to-school evenings, and precious family time together around the table!

Cooking for Two?

This is a very easy recipe to cut in half! Use one box of mac and cheese, one can of tuna, and half a bag of peas. Bake the casserole in an 8-inch square dish. Cooking instructions remain the same.

More Casserole Recipes You Might Like;

3-Ingredient Tuna Casserole

5 from 3 votes
Prep: 15 minutes
Cook: 10 minutes
Total: 25 minutes
Servings 6 servings
Calories 405 kcal
A delicious, nutritious and comforting meal made with only a few pantry staples. This tuna casserole couldn't be easier!


  • 2 10 ounce boxes Horizon Organic Cheddar Cheesy Deluxe Mac and Cheese
  • 2 5 ounce cans tuna in water, drained and flaked with a fork
  • 1 16 ounce bag frozen peas (not thawed)
  • Optional topping: ½ cup Panko breadcrumbs combined with 2 tablespoons melted Horizon Organic butter; sliced green onions


  • Preheat oven to 350F (180C). Spray a 9 x 13-inch baking dish with cooking spray and set aside.
  • Prepare both boxes of mac and cheese according to package instructions. Gently fold in tuna and peas. If the mixture seems a bit dry, add a splash of Horizon Organic milk until it reaches the desired consistency.
  • Pour mac and cheese mixture into prepared baking dish. Cover with foil and heat in the oven for about 10 minutes, or until completely heated through.
  • Remove foil and sprinkle with buttered breadcrumbs, if desired. Return to the oven (uncovered) for 5 more minutes, or until topping is golden brown. Garnish with sliced green onions.


Cooking for Two? This is a very easy recipe to cut in half! Use one box of mac and cheese, one can of tuna, and half a bag of peas. Bake the casserole in an 8-inch square dish. Cooking instructions remain the same.


Serving: 1/6 of the recipeCalories: 405kcalCarbohydrates: 56gProtein: 23gFat: 10.6gSaturated Fat: 2.6gCholesterol: 35mgSodium: 799mgFiber: 5.4gSugar: 10g
Keyword: Pasta Bake, Tuna Casserole, Tuna Pasta
Course: Dinner
Cuisine: American
Author: The Seasoned Mom

This is a sponsored conversation written by me on behalf of Horizon. The opinions and text are all mine.


Hey, I’m Blair!

Welcome to my farmhouse kitchen in the foothills of Virginia’s Blue Ridge Mountains. Inspired by local traditions and seasonal fare, you’ll find plenty of easy, comforting recipes that bring your family together around the table. It’s down-home, country-style cooking!

Read More

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  1. Gayle @ Pumpkin 'N Spice says:

    I can’t believe it’s almost mid September! I am enjoying the cooler temps and fall, too. And this tuna casserole looks amazing! Definitely one of my favorites from childhood! I’m loving that this is just three ingredients. I’ve got to try this, and soon!

    1. Blair says:

      Yep, this casserole is totally a blast from the past (in the BEST way)! 🙂

  2. Ashley says:

    Thanks for not forgetting about the single household folks and providing the cooking for 2 comments on all of your recipes! 🙂 This is super easy and yum looking too!

    1. Blair says:

      Oh, you’re so welcome, Ashley. I’m glad that you find it helpful! I have a lot of readers that are cooking for just one or two, so I aim to please! 🙂

  3. Cindy Brown says:

    Thank you so much for sharing this awesome recipe ! It is super-easy (which is what l like !) , has basic ingredients and and oh-so-tastey ! I made it last night as my Kraft Dinner (Canada)-fan-daughter was joining me for supper . When she came in she was totally confused when she saw a KD box , a can of tuna and a bowl of frozen peas on the cupboard ! Lol !! I made the 1/2 version , topped with the optional breadcrumbs and served with a salad . There was plenty and of leftovers…gotta love leftovers ! This recipe is definitely a keeper and will be making it again soon . ????

    1. Blair says:

      I’m so glad that you enjoyed it, Cindy!! Thanks for letting me know! 🙂

  4. Linda Dodds says:

    Have you ever made this with diced chicken?

    1. Blair says:

      Hi, Linda! No, I haven’t — but I’m sure it would be delicious! I would use an equal amount of cooked, diced chicken and follow the exact same cooking instructions. 🙂

  5. Kay says:

    It’s Ash Wednesday and this is perfect for dinner. It’s always been one of my husband’s favorites. Married 60 years and still going strong. Thanks boo

    1. Blair says:

      Yes, Kay — you’re right, this is perfect for Ash Wednesday!

      Congrats on 60 years of marriage, too. That’s AMAZING! 🙂

    2. Cassidy Watkins says:

      Delicious and very easy too make .

  6. Emily says:

    5 stars
    What an easy recipe and it sounds so comforting and delicious!

    1. Blair says:

      Thanks, Emily!

  7. Johnny Dixon says:

    5 stars
    I have tried your tuna casserole and it is great that you have made dinner more easier then normal mrala.

  8. Jill says:

    It would be a good idea for dinner some time this next week I have to cook dinner for the family next week

  9. Cassidy Watkins says:

    Delicious and very easy too make .

    1. Blair says:

      Thank you, Cassidy!

  10. Dot Zschiesche says:

    What other vegetable besides peas would you recommend. A family member does not like peas.

    1. Blair says:

      Hi, Dot! You can use almost any veggies that you like. If you’re using larger vegetables like broccoli florets, green beans or carrots, you will likely want to steam or boil them until they’re crisp-tender before adding them to the dish. Otherwise you’ll end up with crunchy vegetables. Corn would also work — no pre-cooking necessary. Enjoy!

  11. Christine says:

    5 stars
    Thank you so much for posting a 3 item recipe! I could not find Horizon mac and cheese, so I had to use Annie’s brand – in the 11oz size. I’m not sure if that’s what made the difference, but I would like it to be more cheesy than it was. I saw you recommended adding milk, but I didn’t want to water it down, as my goal was to make it creamier.
    With that said, what would you think about adding a can of condensed cream of mushroom soup to this? And/or some extra grated sharp cheddar? If the cheddar is a go, how much would you say to add?
    TYIA ☺

    1. The Seasoned Mom says:

      Hi Christine! We still recommend adding milk. It will help with the creaminess – especially if you use a higher-fat option. You could try cream of mushroom soup! We haven’t tested it and can’t say how much to add. Start with a splash, and adjust until your desired consistency is achieved. Just be mindful not to make the casserole too runny. We’d love to know how it goes if you give it a try!

      1. Christine says:

        Thank you for the quick reply & your suggestions! My other option would be to skip COMSoup, and instead go with adding shredded sharp cheddar cheese? And, approx how much would you say?
        Again, TYIA, and I will let you know how the option I go with turns out!

        1. The Seasoned Mom says:

          Of course! We probably wouldn’t recommend substituting it with cheese as the casserole will become just melted cheese.