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
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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**
Rachel says
I LOVED this! And both husband and stepkid had 2 helpings each! Total success.
Thank you!
Laurie Ebarb says
I just made this. Yumm!! I tried to keep to your recipe but I used broccoli instead of peas, added more cheese and put all of it in instead of topping it off and broiling it. I try not to turn on the oven in the summer here in Houston! It tastes great, but mine is mushier than what your photo looks like. My cabbage probably cooked too long while I was getting the remaining ingredients prepared.
Oh also, I couldn't find "Lemon Zest" so I used Lemon extract instead. Is it similar?
Peace Love and Low Carb says
Lemon zest is just the rind of the lemon peeled off with a zesting tool.
Meredith says
I'm so excited to see this. I miss tuna casserole enormously!
catherine says
how long does this keep? i made this a few days ago but i dont want it to go to waste and i also dont want to get sick. My husband wont eat it and neither will my son.. i dont know why its freakin delicious.
Peace Love and Low Carb says
If you are worried about it spoiling, you can always freeze it to reheat later.
Peace Love and Low Carb says
If you are worried about it spoiling, you can always freeze it to reheat later.
Lisa says
Do you think you can use almond cream or coconut cream?
Peace Love and Low Carb says
Yes, the sauce just won't be as thick. You may want to add a little xanthan gum to help thicken it.
Kim says
This was so yummy! A gourmet version of my childhood memory. My husband and noodle loving 16 year old kept adding more and more to their plates. There was only a smidge leftover which I gladly ate with lunch the next day. Thanks for the great recipe!
Alison says
Made this, so delicious! I used gruyere. My only question, my cream didn't think as much as I hoped for, but otherwise, love it and making this again and again!
Peace Love and Low Carb says
You can always simmer it a little longer or add a little more cheese to the sauce to help thicken it. So happy you enjoyed it!
Carol Jenkins says
Since my tuna noodle casserole calls for cream of mushroom soup, I just HAD to add mushrooms. I pureed them into the heavy cream. I really like this recipe...my husband did not, but, then, he does not care for tuna noodle casserole either!
Kim (Buffalo / Niagara Falls, NY area) says
Made this last night for dinner. It was yummy and a nice warm comfort meal reminiscent of the old classic. I am sad there were no leftovers for today's lunch! Thank you for a great easy recipe. I prepped my cabbage noodles earlier in the week and used them for spaghetti and meatballs and then I packed up the rest of the cabbage noodles in the fridge to use for this. Will definitely make again. For those that don't like tuna, I think it would be delicious with chicken too. And next time instead of the parm cheese browned on the top, I think I might try some crushed pork rinds.
Tobbe says
Love, love, love your Fried Cabbage with Kielbasa recipe. It's so good!: ) Can't wait to try this. Was always a fan of Mac n Cheese casseroles with tuna. This sounds like a much tastier and healthier alternative 🙂