This Keto Tuna Casserole has all of the classic flavors of a traditional tuna noodle casserole recipe, while being low carb and gluten free. Rich and flavorful cream sauce, with onion, garlic, peas, celery, herbaceous dill, and bright, fresh lemon, paired with shredded cabbage and albacore tuna, then topped with cheese and baked until it is golden brown and bubbly. It's the perfect quick and easy weeknight meal.
Ingredients in Keto Tuna Casserole
Ingredients Notes
- Cabbage: this is what makes this recipe a keto recipe. By using cabbage in place of traditional noodles, you can cut the carbs and the gluten. I've done this in a few other cabbage noodle recipes, like my Cheesy Smoked Sausage and Cabbage Casserole, Fried Cabbage with Kielbasa, and Egg Roll in a Bowl. I use green cabbage, but any can be used: Savoy cabbage, red cabbage, Napa cabbage, even Brussels sprouts! Cut your favorite cabbage into shreds with a knife or mandolin. You can also use coleslaw mix and make this Keto Tuna Casserole even more simple.
- Tuna: for the best taste, I highly recommend using sustainably pole caught albacore, canned in water. You can also use fresh tuna or even canned or fresh salmon. For more tuna recipes, check out these Asian Tuna Cakes and Avocado Tuna Salad.
- Lemon juice and zest: again, fresh is best. The lemon in this recipe really compliments the tuna and adds some bright freshness.
- Dill: fresh herbs are my favorite way to add flavor to any dish. Dill is the perfect compliment to seafood, and tuna is no exception.
- Peas: if you really want to cut down on carbs, you can omit the peas from this recipe entirely, but I recommend keeping them! Fresh peas add a beautiful pop of color and sweetness. You can also used canned peas.
How to Make Keto Tuna Casserole
Step by Step Instructions
STEP 1: First, heat the olive oil and butter in an extra large ovenproof skillet over medium heat.
STEP 2: Next, add the cabbage, onion, celery, garlic, sea salt and black pepper to the pan. Sauté vegetables until they are crisp tender - about 10 minutes.
STEP 3: In a separate bowl, mix in the dill, mustard powder, lemon zest, and lemon juice.
STEP 4: Add the lemon mixture to the pan. Stir to combine.
STEP 5: Pour the heavy cream and 1 cup Parmesan cheese into the pan. Mix in and keep stirring until the cheese has melted and combined with the heavy cream.
STEP 6: Then, reduce heat to medium low. Simmer, allowing the sauce to thicken.
STEP 7: Once the sauce has started to thicken, stir in the tuna and the peas.
STEP 8: Sprinkle the remaining Parmesan over the top of the dish and transfer to the oven. Lastly, broil on high for 3 to 5 minutes or until the Parmesan on top has made a golden brown crust.
Recipe Tips and Variations
- Serving suggestions: I recommend serving this Keto Tuna Casserole with some of my favorite vegetable side dishes: Lemon Pepper Green Beans, Brussels Sprouts with Creamy Dijon Cider Dressing, Balsamic Shallot Mushrooms, or even a simple side salad. You can also add mushrooms to the recipe for a boost of extra veggies.
- Storage: store in the fridge in an airtight container up to 3 days. If you plan to store it in the freezer, you can do so before baking for up to 3 months.
- Reheating: for best results, reheat this low carb tuna casserole on the stove top or in the microwave. You can add a little cream as well to keep it from drying out, especially if reheating in the microwave.
- Low carb noodle substitutions: these are plenty of low carb pasta substitutions: zucchini noodles, Shirataki noodles, rainbow vegetable noodles, and even spaghetti squash would work great in this recipe.
- Protein options: not a fan of tuna? No problem. Try this tuna noodle casserole recipe with fresh chicken, canned chicken, salmon, or shrimp as an alternative protein.
- Shortcuts: to make this tuna casserole dish even faster, you can use a canned cream of mushroom soup for the sauce and coleslaw mix instead of shredded cabbage. However, using canned soup will increase the carbs quite a bit.
- Crispy fried onion topping: this adds a great textural contrast. I outline how to make a low carb version of crispy fried onions in this recipe.
- Cheese it up: add sharp cheddar to really drive up the cheesy goodness of this recipe.
- Breadcrumb topping: add a layer of crunch without the carbs or the gluten. Try topping this Keto Tuna Casserole with grated parmesan or my nut free breading mix.
Frequently Asked Questions
Cook the veggies and aromatics in olive oil and butter until just tender, mix in the seasonings, add heavy cream and Parmesan for a creamy element, and let it all thicken. Finally, add the tuna and peas, sprinkle extra Parmesan on the casserole, and bake until it reaches golden, bubbly perfection.
Classic homemade tuna noodle casserole uses pasta as the basis, and a small serving will have at least 22g of carbs. This is a Keto Tuna Casserole, so there are only 7g net carbs per serving.
Some great options for low carb pasta are Shirataki noodles, spaghetti squash, zucchini noodles, or even cauliflower.
More Keto Recipes
REVIEW AND FOLLOW: Have you tried this recipe? If so, please leave a comment and ⭐️ rating below. If you make our recipes and share them, be sure to use our hashtag #peaceloveandlowcarb on social! We love seeing what you are making. FOLLOW us on FACEBOOK | INSTAGRAM | PINTEREST for more delicious recipes.
Keto Tuna Casserole
- Total Time: 45 minutes
- Yield: Makes 8 Servings 1x
- Diet: Gluten Free
Description
This Keto Tuna Casserole has all of the classic flavors of a traditional tuna noodle casserole recipe, while being low carb and gluten free. Rich and flavorful cream sauce, with onion, garlic, peas, celery, herbaceous dill, and bright, fresh lemon, paired with shredded cabbage and albacore tuna, then topped with cheese and baked until it is golden brown and bubbly. It's the perfect quick and easy weeknight meal.
Ingredients
- 2 tablespoons olive oil (I use this brand) code kyndraholley for $5 off
- 2 tablespoons butter
- medium head green cabbage (about 1 ½ lbs), cut into large shreds
- 1 cup chopped onion
- 3 ribs celery, chopped
- 2 cloves garlic, minced
- sea salt and black pepper, to taste
- 2 teaspoons dried dill or 2 tablespoons fresh dill
- 2 teaspoons dry mustard powder
- 1 tablespoon lemon zest
- juice of 1 lemon
- 1 ½ cups heavy cream
- 1 ¼ cups grated Parmesan cheese, divided
- 3 - 5oz cans albacore tuna, drained
- ½ cup frozen peas
Instructions
- Heat the olive oil and butter in an extra large ovenproof skillet over medium heat.
- Once heated, add the cabbage, onion, celery, garlic, sea salt and black pepper to the pan.
- Sauté until the vegetables are crisp tender - about 10 minutes.
- Mix in the dill, mustard powder, lemon zest, and lemon juice.
- Pour the heavy cream and 1 cup Parmesan cheese into the pan. Mix in and keep stirring until the cheese has melted and combined with the heavy cream.
- Reduce heat to medium low and let simmer to allow the sauce to thicken.
- Once the sauce has started to thicken, stir in the tuna and the peas.
- Sprinkle the remaining Parmesan over the top of the dish and transfer to the oven.
- Broil on high for 3-5 minutes or until the Parmesan on top has made a golden brown crust.
Notes
- net carbs per serving: 7g
- Storage: store in the fridge in an airtight container up to 3 days. If you plan to store it in the freezer, you can do so before baking for up to 3 months.
- Reheating: for best results, reheat this low carb tuna casserole on the stove top or in the microwave. You can add a little cream as well to keep it from drying out, especially if reheating in the microwave.
- Low carb noodle substitutions: these are plenty of low carb pasta substitutions: zucchini noodles, Shirataki noodles, rainbow vegetable noodles, and even spaghetti squash would work great in this recipe.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
- Category: Casserole Recipes
- Method: Saute
- Cuisine: American
Nutrition
- Serving Size: ⅛th of the recipe
- Calories: 377
- Fat: 28g
- Carbohydrates: 10g
- Fiber: 3g
- Protein: 23.5g
**Recipe originally posted October 24th 2016 - Updated May 14th 2021**
LD Kay says
Made this last night. Followed recipe as written. My husband and I both loved it. So much that we finished the leftovers for lunch today. We will be making again for sure. Thanks for writing a recipe that works beautifully as written. You did a great job! I will look up more of your work.
Kori says
Amazing! I just made this and it is absolutely scrumptious!!! Full of iron too! Thank you! I have officially pinned this to my tried and true board. Next time I will be adding more cheese however, just to thicken up the sauce a bit more, but phenomenal!
Tina says
I was having "one of those days" and wanted an easy to make comfort dish, but didn't want to leave low carb behind. I found your recipe and feel like I've discovered another world. It is so much better than traditional tuna casserole! This will be part of our regular meal plan for sure. Thank you for such an amazing dish! (i like the idea of adding a bit of mushroom)
TychaBrahe says
I'm going to be the person who says I changed up the entire recipe.
My tuna casserole recipe involves a massive amounts of extra sharp cheddar. I chose to make the recipe more like the way I'd make my usual tuna casserole. I cooked the cabbage and veggies in one pot, made the cream and Parmesan sauce in another, and then built the casserole in a baking dish with half the cabbage, half the cheese sauce, and half of 8 ounces of grated cheddar, repeat. Sprinkle a dash of paprika on top, and bake in a 350° oven for about 45 minutes. It was amazing!
The next time I make this, I will mix the onions and celery into the cheese sauce, as if I had used cream of mushroom soup.
Carol says
This was so yummy!! I will be making again for sure!!
Jillann says
I was craving my mom's tuna hotdish that uses Campbell's nacho cheese. I might add some spice to the receipe next time. This hit the spot and it was so delicious!!!
I will be making this again soon, thank you so much.
Nicole Holdridge says
It's insane how good this is. All the flavors are so yummy, I especially love the lemon. I'm a huge fan of dairy also! Gotta help out people that are struggling so much, yet working so hard!
Thank you for this recipe, will certainly be a family fav!
John says
This is amazing! Tuna casserole has always been a guilty comfort food pleasure, and when I went no carb I assumed I’d never have it again. Wrong! I’ve made this a few times. To me the trick is evaporating enough liquid so the casserole isn’t watery, without over cooking the cabbage so it still has texture. My solution is to cook the cabbage and pour into a bowl before it is too soft. Then make the cream sauce (I add mushrooms to mimic mushroom soup), and pour in the accumulated liquid from the cabbage—there is a lot—and reduce till thick. I also add in some shredded cheddar when tossing it all together with the sauce before pouring back into the skillet to bake. Tastes just like traditional tuna casserole! Thanks so much!
Laura says
I made this a little while ago and it is DELICIOUS; almost dangerously so because I just kept wanting to eat it!
I was wondering what you think about a crockpot version of this..?
Thanks for another amazing recipe!
Pam says
To Laura. Not good for a crock pot. It will be too watery & mushy. You have to reduce the cream for the right consistency.
Jennifer Barnett says
I made this last night and I’m counting the minutes until I can dig into the leftovers. To make it more like the tuna noodle my mom would make while I was growing up I substituted the onion for some very small mushrooms and instead of topping with Parmesan I topped it with shredded cheddar cheese and sprinkled some crushed pork rinds on top. I also left out the lemon zest. It turned out amazing and took me right back to my moms kitchen!