Can I use fresh tuna instead of canned?

Absolutely. Simply sear fresh tuna, flake it, and proceed with the recipe. Keep in mind that you might need to season it more, as fresh tuna has a milder taste than what you’d find in a standard tuna casserole with mayo.

What other cheeses can I substitute for Gruyere?

Cheddar, Monterey Jack, or even mozzarella can work in this easy keto tuna casserole. Gruyere adds a nutty depth, but feel free to experiment with your favorites.

Can I add vegetables to this keto tuna casserole recipe?

Definitely. Low-carb veggies like mushrooms, spinach, or zucchini pair wonderfully. Just sauté or steam them first so they don’t release extra water in your keto tuna casserole.

Is there a way to make it creamier without increasing carbs?

You can add a bit of heavy cream or cream cheese. Both options enhance the velvety texture of your tuna casserole with mayo without adding too many carbs.

How can I reduce the fishy taste of tuna?

If you’re sensitive to tuna flavor, blend in extra spices or aromatic ingredients like garlic and herbs. Also, rinsing and draining your tuna thoroughly can help soften the intensity in this keto tuna casserole recipe.

Keto Tuna Casserole: Quick, Indulgent & Deliciously Low-Carb!

Quick Keto Tuna Casserole: Deliciously Low-Carb!

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This irresistibly creamy keto tuna casserole is a low-carb twist on a classic. It combines succulent tuna, velvety mayonnaise, tender riced cauliflower, and a golden layer of Gruyere cheese. The result is a comforting dish that’s both nostalgic and health-conscious, perfect for weeknights or gatherings.

Author: Maren Varden
Prep Time: 10 minutes
Cook Time: 25 minutes
Total Time: 35 minutes
Yield: 4 servings 1x
Category: Dinner
Method: Baking
Cuisine: American

Ingredients

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- 2 (5-ounce) cans tuna in water, drained and flaked
- 1 cup (100g) cooked riced cauliflower
- ½ cup (120g) mayonnaise
- 1 tablespoon (15ml) Dijon mustard
- ½ cup (50g) shredded Gruyere cheese, divided
- ¼ cup (40g) red onion, minced
- ¼ teaspoon (1.25g) sea salt
- ¼ teaspoon (1.25g) black pepper
- ¼ teaspoon (0.5g) cayenne pepper
- ¼ cup (15g) parsley, chopped (garnish)

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Instructions

Preheat the Oven: Preheat your oven to 375°F (190°C).
Mix the Base: In a bowl, combine the drained tuna, cooked riced cauliflower, and minced red onion.
Make the Sauce: Whisk together mayonnaise, Dijon mustard, half of the Gruyere, salt, black pepper, and cayenne.
Combine Everything: Pour the sauce over the tuna mixture and fold until fully coated.
Assemble the Casserole: Transfer to a greased casserole dish and smooth the top.
Bake Until Golden: Sprinkle the remaining Gruyere on top and bake for 20–25 minutes until golden and bubbly.
Rest & Serve: Let it rest for 5 minutes, garnish with parsley, and serve warm.

Notes

Drain Tuna Thoroughly: Too much moisture can make the casserole watery. Press excess liquid out with a paper towel before mixing.
Use Full-Fat Mayo: For the creamiest texture, opt for full-fat mayonnaise. Low-fat versions may result in a thinner sauce.
Don’t Overbake: Overbaking can dry out the tuna. Remove from the oven when the cheese is bubbly and golden brown.

Nutrition

Serving Size: 1 portion
Calories: 320 kcal
Sugar: 2g
Sodium: 680mg
Fat: 24g
Saturated Fat: 6g
Unsaturated Fat: 14g
Trans Fat: 0g
Carbohydrates: 3g
Fiber: 1g
Protein: 20g
Cholesterol: 45mg

Find it online: https://www.simplitasty.com/keto-tuna-casserole-recipe/