This keto tuna casserole is a true winner, it is easy, delicious, and nutritious! Picture this: tender chunks of canned tuna, vibrant florets of broccoli, and a luscious, creamy cheese sauce coming together into a bubbling, cheesy goodness! If you are on the lookout for a scrumptious low-carb dish, this hearty casserole is sure to satisfy. Get ready to savor the creamy decadence and wholesome goodness that await in every comforting bite!
Why we love this recipe!
- Budget friendly dinner using canned tuna and other basic ingredients.
- Only simple steps are required with no special equipment needed.
- Versatile – swap the tuna for shredded chicken, or change the veggies.
- The deliciously creamy, cheesy sauce makes it very family friendly.
What you will need to make this recipe
We love using canned tuna in our weeknight dinners because it is packed with protein, budget-friendly, and delicious! You only need basic grocery-store ingredients to make this keto tuna casserole, which you may already have in the fridge or pantry.
- Heavy whipping cream – Heavy whipping cream works best in this recipe. In Australia, we use pure cream or thickened cream.
- Cream cheese – We use block-style full-fat cream cheese in this recipe.
- Butter – Salted butter works fine in this recipe.
- Parmesan cheese – We like to use finely grated parmesan cheese in this recipe the cheese sauce is creamy. It adds loads of flavor too!
- Garlic powder – For convenience, we like to use garlic powder in this recipe, but fresh minced garlic would also work for a stronger garlic flavor.
- Cayenne pepper – This is optional, but it does add a nice subtle flavor to the cheese sauce.
- Salt and pepper
- Canned tuna – We prefer to use canned tuna in springwater in this recipe. Make sure it is well drained and then broken up into flakes.
- Broccoli – Fresh or frozen broccoli florets both work in this recipe.
- Shredded cheese – We like to use shredded cheddar cheese in this recipe, but you can use your preferred cheese. Colby, mozzarella, or shredded cheese blends would work well.
Equipment
Disclosure: The above post may contain affiliate links. We may earn a small commission from purchases made through these links, at no additional cost to you. Everything we recommend on our website are products we use and love. Thank you for supporting Have Butter will Travel and allowing us to share our low carb experiences with you.
You may need,
Step by Step Instructions
This recipe is so delicious as it uses the best cheese sauce recipe on the internet! This cheese sauce recipe is simple to make and is the key to the flavor and creaminess of this keto tuna mornay recipe. Once you have the cheese sauce made and steamed the broccoli, it is as simple as putting it all in a baking dish and topping it with cheese, and baking it in the oven.
- Prepare the ingredients for the cheese sauce.
- Place all ingredients in a saucepan and whisk together until smooth. Simmer to allow it to thicken slightly.
- Steam the broccoli florets
- Start assembling the tuna casserole by placing the steamed broccoli in the bottom of a casserole dish in an even layer.
- Drain the tuna and then flake it in an even layer over the broccoli.
- Pour the cheese sauce over the broccoli and tuna, trying to cover the top later completely.
- Sprinkle the shredded cheese evenly over the top of the cheese sauce. Baking in the oven until golden brown and bubbling.
- Remove from the oven and allow to rest for 5 minutes before serving.
Delicious low carb tuna recipes
We love tuna and it is a fantastic source of protein on a low carb lifestyle. Canned tuna is also readily available in most grocery stores and budget friendly. It is quick and easy to make for packed lunches and perfect for use in meal prep.
Here are some of our other favourite low carb tuna recipes;
- Keto tuna salad lettuce cups
- Tuna salad without mayo
- Keto tuna patties
- Mexican tuna salad
- Keto tuna poke bowl
Expert tips, suggestions & how to store
- Keto chicken casserole – If you are not a fan of tuna or have some leftover shredded chicken, this recipe also works really well with shredded chicken in place of the tuna.
- Broccoli alternatives – You can substitute other cooked veggies in place of the broccoli. We like a combination of steamed broccoli and cauliflower.
- Make ahead – If you like to meal prep you can make the cheese sauce and steam the broccoli ahead of time and then assemble the casserole prior to cooking.
- Storage – The cooked keto tuna casserole will keep in the fridge for 4-5 days. We like to store it in Pyrex storage containers. It reheats well in the microwave or covered in the oven.
- Serving suggestions – As this meal contains a lot of protein and veggies we find it is a complete meal. You can also serve it with additional veggies or a side salad if you prefer.
FAQ’s
Canned tuna is perfect for a keto diet as it is packed with protein and has no carbohydrates. We prefer canned tuna in springwater or plain olive oil without any flavorings, we can then add our own preferred flavors.
Canned tuna that is unflavored and packed in springwater or olive oil has zero carbohydrates, so is keto-friendly. Fresh tuna also has zero carbs.
A traditional homemade tuna casserole usually contains pasta or rice and is at least 25g of carbohydrates per serve depending on the recipe and serving size. This keto tuna casserole only has 9g of total carbohydrates for a whole meal.
No, tuna by itself has very low to zero carbohydrates.
If you like this recipe you may also like…
- Teriyaki Chicken Rice Bowl
- Mexican Chicken Salad
- Mexican tuna salad
- Tuna Salad without Mayo
- Panko Chicken
- Cream Cheese Pasta
- Lemon Chicken Marinade
- Mexican chicken marinade
- Smoked Chicken Salad
- Tandoori Chicken Salad
Ingredients
Keto Cheese Sauce
- 1 cup heavy whipping cream
- 4 oz cream cheese, cubed (115g)
- 1 oz butter, cubed (30g)
- ¼ cup parmesan cheese, finely grated
- ½ tsp garlic powder
- 1-2 pinches cayenne pepper
- salt & pepper
Tuna Casserole Assembly
- 12 oz broccoli florets (350g)
- 4 cans tuna, drained (4 x 5oz cans) (450g)
- 4 oz cheddar cheese, shredded (115g)
Instructions
Keto Cheese Sauce
- Add all ingredients to a small saucepan and heat over medium.
- Whisk to combine and let simmer for a few minutes to combine and thicken slightly.
- Season with salt and pepper to taste.
Tuna Casserole Assembly
- Preheat oven to 350F/180C.
- Steam broccoli florets until just tender, don't overcook as they will cook a little more in the oven.
- Arrange broccoli in an oven-proof dish, sprinkle over tuna evenly. Pour over the prepared cheese sauce and sprinkle with grated cheese.
- Bake for 15-20 mins until golden on top and bubbling. Allow to cool for 5 mins before serving.
Video
Notes
-
- Keto chicken casserole – If you are not a fan of tuna or have some leftover shredded chicken, this recipe also works really well with shredded chicken in place of the tuna.
-
- Broccoli alternatives – You can substitute other cooked veggies in place of the broccoli. We like a combination of steamed broccoli and cauliflower.
-
- Make ahead – If you like to meal prep you can make the cheese sauce and steam the broccoli ahead of time and then assemble the casserole prior to cooking.
-
- Storage – The cooked keto tuna casserole will keep in the fridge for 4-5 days. We like to store it in pyrex storage containers. It reheats well in the microwave or covered in the oven.
-
- Serving suggestions – As this meal contains a lot of protein and veggies we find it is a complete meal. You can also serve it with additional veggies or a side salad if you prefer.
Nutrition Per Serve
Super easy and really delicious for keto and non-keto family members.
Thanks so much julie
love at first bite (well, first lick- I licked the sauce pot clean! 😌) I love love LOVE this recipe! thanks so much for such a yummy dinner! I will make mushroom and onion cauliflower rice to go with it next time! 😋
So glad you love this recipe. It’s definitely one of our favourites
Love this! So quick, easy and delicious 😋
Thanks Lynda
Made this for dinner and it was delicious! Kids also loved it. Will definitely be making again!
It’s delicious
This was absolutely delishious. I never like tuna casserole while growing up. However, I’m now low carb and looking for keto comfort food. This fits the bill perfectly. Thank you! ( And I can see other usesfor that cheese sauce going forward!)
We absolutely love this recipe. We have been having it a bit lately.
Hi, so I just want to know if the Nutritional Facts are based on both the Tuna Bake and/with the Cheese Sauce together or separately? 😊
It is delicious!
The nutritional info includes both.
This is fantastic! Made it for lunch today. Will definitely be making again. Thanks for a great recipe!
Awesome. Thank you.
This is delicious my second time making it we love it 😍
Thanks Cindy.
I was looking for an easy keto cheese sauce, and happened upon the Tuna Mornay. I got a twofer, a great tasting cheese sauce and a delicious casserole. Thanks for sharing your recipes.
I love that. A twofer!!!
This is delicious. A weekly offering in our house. A childhood memory now in the keto world. Winner winner Tuna dinner.
Love it. Winner winner tuna dinner.
Where do I get the cheese what kind of cheese do I get
We just use tasty or cheddar cheese from the supermarket.
We loved this tuna mornay. Even my non-keto other half like it, said it was ‘nice and cheesy’. He didn’t even miss the pasta and corn that I used to make it with! That cheese sauce makes everything better 🙂
I agree, the cheese sauce is the highlight of this recipe.
This is a weekly favourite in our home now! It’s so quick and easy!
I steam the broccoli in the thermomix at the same time as the cheese sauce is cooking and then throw is all in oven.
It’s so quick and nutritious and the whole family love it and they’ve stopped asked about the tuna pasta we used to eat in my pre-keto days!!!!
I love stories like this. Thanks Narelle.
This was delicious!
Thanks Brooke.
This looks wonderful! I plan on making this tonight.
It’s really good. Hope you enjoy it.
I made this recipe last week. Let me tell you, it was so delicious my husband and I ate the whole thing! Wow!! Thank you for the super, awesomely delicious recipe. I think my tastebuds were secretly singing. 😋 This will definitely be a recipe we keep. 🙌
So glad you liked the tuna Mornay. It’s my favourite way to consume the cheese sauce, which is delicious.
Made this tonight and it was soupy. Where did I go wrong? The flavor was amazing.
Hi Emily,
A couple of things may have happened. Was the cheese sauce thick when you added it to the tuna and vegetables? If not, the sauce needed to thicken on the stovetop more. If it was, it may have been from water coming out of the vegetables. We usually use broccoli and this hasnt been an issue for us. Another tip from Erika would be to maybe let the dish sit for 5 minutes when you take it out of the oven before serving. Also, make sure you have drained the tuna well before putting it in the baking dish. Hope this helps.
Thanks Dan
Does this really have 10 g. of carbs? I don’t see hwere they are coming from.
Yes it has 9 total carbs and 7 net. The carbs comes from the broccoli, all the cheeses and the cream in the cheese sauce. Cheese and cream have a small amount of carbs and they all add up in this recipe. We were actually shocked when we made it as to how many carbs it had.
Yes, Yummy!! Thank you for this fast dinner.
I found that 4 servings was way too much too eat and divided my casserole dish into 8 servings. I rarely eat a/4 head of broccoli in 1 meal :), so my net carbs are 3.8.
Sounds perfect. Glad you enjoyed it.
Wow!!! This was absolutely D-E-L-I-C-I-O-U-S!! Thank you so much for sharing this recipe ❤️ Fussy kids and husband demolished it 😊
That cheese sauce… I have no civilised words for how good it is haha.
So glad you enjoyed the tuna Mornay. We tried to give it to our niece and nephew and they were not interested. They must be even fussier than your kids.
Omg just had this for dinner… sooo yummy! Just the right amount of tuna and broccoli to cheesyness. Definitely a new favourite!
Thank you so much for your comment Rachel! So glad you enjoyed it. One of our favourites too
Just made this tonight and it was delicious! I’ve tried a few keto casseroles and this is the first one that didn’t feel like I was just eating a bunch of butter and cheese (even though there was a hefty amount of cheese :P) . Loved the big chunks of broccoli and that keto cheese sauce is so goooood.
Thank you so much Bhumi. We are big fans of that cheese sauce too. We haven’t had this Tuna Mornay for awhile and we have added to the dinner list for this week.