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Easy Keto Tuna Casserole Recipe 🥘

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Are you ready to try something super cool? Our amazing Keto Tuna Casserole recipe is about to blow your mind! We gave the beloved classic a low-carb twist, perfect for your keto lifestyle. It's packed with all the delicious flavors of savory tuna, creamy cheese, and flavorful veggies.

Homemade tuna casserole.
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Preparation and cooking overview

It's an Easy Tuna Casserole Recipe that takes only 45 minutes to prepare. Sauté some flavorful veggies and zucchini noodles. Combine them with tuna, cream, and herbs, then bake them with almond meal and cheese. And that's it! You have a perfect casserole dish!

Chef's note

Don't be afraid to play around with the ingredients. Dice some bell peppers and toss them into the skillet for an extra crunch! If you love spicy food, sprinkle red pepper flakes or smoked paprika on the casserole. You can even swap the Parmesan with Asiago or Romano for a different cheese flavor.

  • Prep Time: 10 minutes
  • Cooking Time: 30 minutes
  • Total Time: 40 Minutes
  • Difficulty Level: Easy
  • Recipe Makes 2 Servings

🥘 Ingredients for this keto tuna casserole recipe

Our cheesy tuna casserole might look like a complicated dish with many stellar ingredients. But don't be fooled — we only need a handful of kitchen staples to make a Low Carb Tuna Casserole!

  • 1 can of tuna, drained
  • 1 medium zucchini (cut into noodle shapes: zoodles)
  • ½ cup chopped mushrooms, medium diced
  • ¼ cup onions, small diced
  • ¼ cup celery, small diced
  • 1 clove garlic, minced
  • ½ cup chicken or vegetable broth
  • ½ cup heavy cream
  • ¼ cup Parmesan cheese, grated
  • ¼ teaspoon dried thyme
  • ¼ teaspoon dried oregano
  • ¼ teaspoon paprika
  • 2 tablespoons olive oil
  • ¼ cup almond meal
  • Sea salt and freshly cracked black pepper to taste
  • 1 tablespoon chopped fresh parsley, to serve
Ingredients made ready on the kitchen table for tuna casserole recipe.

Ingredient substitutions

Don't worry if you don't have all the listed ingredients; swap some with these keto-friendly alternatives.

  • Heavy cream: If you don't like heavy cream, use full-fat coconut milk as a dairy-free substitute.
  • Almond meal: Use crushed pork rinds instead of almond meal for a crunchy topping.
  • Parmesan cheese: Feel free to use cheddar or mozzarella cheese instead of Parmesan. They also add a creamy and gooey texture.
  • Chicken or vegetable broth: If you have beef broth in the pantry, use it instead of chicken or vegetable broth.

Additional ingredients

It's always exciting to jazz up a recipe with some extra flavors. Here are some optional keto-friendly ingredients to add:

  • Parsley or dill: Garnish the casserole with chopped fresh parsley or dill for a refreshing note.
  • Bacon bits: Fry a few bacon slices, crumble, and sprinkle them over the casserole before baking. It adds a fantastic crunch and a savory taste.
  • Chopped bell peppers: Add chopped bell peppers to the skillet when you're sautéing the onions and celery.
  • Cherry tomatoes: Halve cherry tomatoes and toss them in when you add the zucchini noodles.
  • Pork rinds: Add some pork rinds with the almond meal if you love crunchy toppings.
Baked tuna casserole recipe.

Cooking tools required

To make this Keto Tuna Casserole recipe, you will need the following cooking tools:

  • Julienne peeler
  • Knife
  • Cutting board
  • Cast-iron skillet
  • Baking dish (casserole)
  • Grater

Tools substitute options

  • Julienne peeler: A standard vegetable peeler works fine to create perfect zoodles. You'll end up with wider, flatter zucchini strips, but they'll still be delicious.
  • Grater: Don't have a grater? Finely chop the Parmesan cheese with a sharp chef's knife.
  • Cast-iron skillet: Use a heavy-bottomed pan instead of a cast-iron skillet.
  • Casserole dish: Replace it with an oven-safe pie dish or Dutch oven large enough to hold all the ingredients.
Tuna casserole on a baking dish.

How to make Keto Tuna Casserole: step-by-step guide

Cooking methods

  • Sautéing
  • Baking

Preparation steps

  1. Gather all your ingredients in the required quantity.
  2. Using a julienne peeler, turn that zucchini into long, noodle-like strips (aka zoodles).
  3. Wash your mushrooms, parsley, and celery with tap water, and chop them finely.
  4. Grate the Parmesan cheese and mince the garlic cloves.
  5. Drain the tuna and set it aside.

Cooking instructions

  1. Preheat the oven to 375°F (190°C).
  2. Heat olive oil in a cast-iron skillet over medium-high heat.
  3. Sizzle the onions and celery for about 3-4 minutes until they become tender and fragrant.
  4. Add the mushrooms to the skillet and cook for 2-3 minutes until they release moisture.
  5. Once the mushrooms are brown, toss in the zucchini noodles. Cook for about 2-3 minutes until they are soft.
  6. Then, add the drained tuna and stir to combine with the veggies. Also, add dried thyme, oregano, paprika, salt, and pepper to the mix.
  7. Now, pour the chicken broth and heavy cream into the skillet. Stir well to combine all the ingredients.
  8. Once done, remove the skillet from the heat. Transfer the mixture to the casserole dish and spread it evenly.
  9. Then, place half of the grated Parmesan over the tuna mixture. Next, sprinkle the almond meal evenly and top it with the remaining cheese.
  10. Transfer the dish to the oven and bake for 20 minutes until the top is golden brown and bubbly.
  11. Remove the casserole from the oven and let it cool for a few minutes before serving.
Sautéing sliced veggies in a cast iron skillet.
Cooking tuna and vegetables in a skillet.
Chicken broth and heavy cream added to a skillet containing tuna and vegetables.
Transferring the cooked tuna and vegetables to a baking dish.
Topping the tuna mixture with parmesan cheese.
Baked tuna casserole in a baking dish.

Chef's pro tip

No one likes a watery casserole. To avoid that, lightly sauté your zoodles until they're slightly softened but firm. And drain your canned tuna thoroughly to get rid of extra liquid. That way, your casserole will remain perfectly creamy, not watery.

What to serve with keto tuna casserole?

Pair this casserole with a keto-friendly side dish to make up for delicious low-carb tuna meals. We have plenty of options:

  • Side salad: Serve the delicacy with a side salad of leafy greens, cherry tomatoes, cucumber, and a light vinaigrette. The combo makes a complete meal.
  • Roasted asparagus: This low-carb veggie works beautifully with the delicious casserole. Its sweet taste is worth a try.
  • Cauliflower rice: The low-carb alternative to traditional rice is a perfect dish to absorb the flavors from the casserole.
  • Steamed broccoli: Steam some broccoli and pair it with this dish for a fresh and crunchy texture.
Topping the baked tuna casserole with fresh parsley.

How to make it healthier?

  • Increase the variety of veggies in the casserole. Add baby spinach, bell peppers, and broccoli.
  • Use organic ingredients wherever possible.
  • Opt for a low-sodium broth to reduce salt and reduce the added salt. You can even prepare the chicken broth yourself to control salt content.
  • Buy tuna packed in water rather than oil.

Time-saving tips

  • If you're pressed for time, buy pre-spiralized zucchini from the grocery store.
  • Buy the broth from the store instead of making it yourself.
Low carb tuna casserole.

What can I prepare ahead of time?

  • Zoodles: Make the zoodles and store them in an airtight container in the fridge.
  • Broth: Prepare the vegetable or chicken broth and store it in a jar in the fridge.

Storage and reheating instructions

Storage tips

Storing and reheating tuna casserole is a breeze. It tastes better every minute it sits in the fridge. So, if you have leftovers, allow them to cool and store them.

  • Refrigerator: Place the leftovers in an airtight box. They will keep for 3-4 days in the fridge.
  • Freezer: Wrap the dish tightly to avoid freezer burn. Store it in a freezer-safe bag, and it will last for up to 3 months.

Reheating instructions

  • Oven: Place the desired portion in an oven-safe dish. Then cover it with foil, and warm it in a preheated oven at 350°F (175°C) until heated.
  • Microwave: Transfer a serving to a microwave-safe dish, cover, and heat for 1-2 minutes. Stir and continue heating the dish in 30-second intervals until hot.
Tuna casserole recipe.

Recipe wrap-up and conclusion

Our Keto Tuna Casserole is perfect for a comforting dinner, healthy lunch, and even a satisfying snack. Every bite is a burst of keto magic, from the sautéed veggies to the creamy goodness. So, grab a fork and indulge in this tasty low-carb delight!

Are you a fish lover? If yes, then our delicious keto fish recipes will amaze you! Check them out now:

Frequently asked questions

Yes, you can! But note that the tuna in oil will add more fat to the recipe. So, drain the oil from the tuna before sautéing.

It is not, but you can make it dairy-free with few substitutions. In place of the heavy cream, use full-fat coconut milk. As for the Parmesan cheese, use nutritional yeast or a dairy-free cheese substitute.

Of course, but you will have to cook it first. Season a tuna steak with salt and pepper. Then, sear it on both sides in a hot skillet. Once done, flake it apart with a fork to resemble the chunky texture of canned tuna.

Canned salmon or cooked chicken breast work fine for this recipe. Both options provide a similar texture.

Absolutely! This recipe is perfect for a one-pot dish. Cook the casserole ingredients in a large ovenproof skillet. Then, top it with cheese and almond meal and bake it in the oven.

We don't recommend using pre-shredded cheese. Using pre-shredded cheese will save you time, but it won't melt nicely.

📖 Recipe

Keto tuna casserole.

Keto Tuna Casserole

Experience the comforting flavors of a classic Tuna Casserole with a keto twist - creamy tuna, savory veggies, and melted cheese come together in this delicious low-carb dish.
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Course: Main Course
Cuisine: American
Keyword: keto casserole, Keto Tuna Dish, Tuna Casserole
Prep Time: 10 minutes
Cook Time: 30 minutes
Total Time: 40 minutes
Servings: 2
Calories: 607kcal

Ingredients

  • 1 can of tuna drained
  • 1 medium zucchini cut into noodle shapes: zoodles
  • ½ cup chopped mushrooms medium diced
  • ¼ cup onions small diced
  • ¼ cup celery small diced
  • 1 clove garlic minced
  • ½ cup chicken or vegetable broth
  • ½ cup heavy cream
  • ¼ cup Parmesan cheese grated
  • ¼ teaspoon dried thyme
  • ¼ teaspoon dried oregano
  • ¼ teaspoon paprika
  • 2 tablespoons olive oil
  • ¼ cup almond meal
  • Salt and pepper to taste
  • 1 tablespoon chopped fresh parsley to serve
US Customary - Metric

Instructions

  • Preheat the oven at 375°F(190°C)
  • Heat olive oil in a cast-iron skillet over medium-high heat.
  • Sizzle the onions and celery for about 3-4 minutes until they become tender and fragrant.
  • Add the mushrooms to the skillet and cook for 2-3 minutes until they release moisture.
  • Once the mushrooms are brown, toss in the zucchini noodles. Cook for about 2-3 minutes until they are soft.
  • Then, add the drained tuna and stir to combine with the veggies. Also, put dried thyme, oregano, paprika, salt, and pepper in the mix.
  • Now, pour the chicken broth and heavy cream into the skillet. Stir well to combine all the ingredients.
  • Once done, remove the skillet from the heat. Transfer the mixture to the casserole dish and spread it evenly.
  • Then, place half of the grated Parmesan over the tuna mixture. Next, sprinkle the almond meal evenly and top it with the remaining cheese.
  • Transfer the dish to the oven and bake for 20 minutes until the top is golden brown and bubbly.
  • Remove the casserole from the oven and let it cool for a few minutes before serving.

Video

Nutrition

Nutrition Facts
Keto Tuna Casserole
Amount Per Serving
Calories 607 Calories from Fat 423
% Daily Value*
Fat 47g72%
Saturated Fat 19g119%
Trans Fat 0.01g
Polyunsaturated Fat 3g
Monounsaturated Fat 17g
Cholesterol 109mg36%
Sodium 298mg13%
Potassium 1010mg29%
Carbohydrates 16g5%
Fiber 5g21%
Sugar 7g8%
Protein 34g68%
Vitamin A 1577IU32%
Vitamin C 23mg28%
Calcium 261mg26%
Iron 3mg17%
*

Nutritional values are estimates only and do not include carbs from sugar alcohols.

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