Mediterranean Keto Tuna Casserole
This Mediterranean Keto Tuna Casserole is a rich and flavorful low-carb twist on the classic comfort dish. It features flaky tuna, tender cauliflower rice, briny olives, sweet peas, and sun-dried tomatoes all wrapped in a creamy, cheesy sauce. Baked until golden and bubbly, it’s a satisfying and nutritious one-dish meal that’s perfect for a keto-friendly dinner or meal prep. Simple to make and loaded with Mediterranean flair, it delivers both taste and texture in every bite.
Total Time
Prep Time: 10 minutes
Cook Time: 25 minutes
Total Time: 35 minutes
Ingredients
2 cans tuna in water, drained (5 ounces each)
2 cups riced cauliflower
1/2 cup baby spinach, chopped
1/4 cup red onion, finely diced
1/4 cup sun-dried tomatoes, chopped
1/4 cup black olives, sliced
1/2 cup green peas (fresh or thawed frozen)
1/2 cup shredded mozzarella cheese
1/4 cup grated Parmesan cheese
1/2 cup full-fat sour cream
1/4 cup mayonnaise
2 tablespoons cream cheese, softened
1 teaspoon dried oregano
1/2 teaspoon garlic powder
1/4 teaspoon black pepper
Salt to taste
1 tablespoon olive oil (for sautéing)
Optional: chopped parsley or fresh basil for garnish
Instructions
Preheat Oven
Preheat your oven to 375°F (190°C). Lightly grease a medium casserole dish and set aside.
Cook Cauliflower Rice
Heat olive oil in a skillet over medium heat. Add the riced cauliflower and sauté for about 5 minutes, until slightly tender. Remove from heat.
Sauté Spinach and Onion
In the same skillet, sauté the red onion and chopped spinach for 2–3 minutes until wilted and fragrant.
Mix Base Ingredients
In a large mixing bowl, combine the tuna, cooked cauliflower rice, sautéed vegetables, sun-dried tomatoes, black olives, and peas.
Make Creamy Sauce
Add the sour cream, mayonnaise, cream cheese, oregano, garlic powder, black pepper, and salt. Stir until the mixture is evenly combined.
Assemble Casserole
Transfer the mixture to the prepared casserole dish. Sprinkle the mozzarella and Parmesan cheese evenly over the top.
Bake
Bake for 20–25 minutes, or until the top is golden brown and bubbly.
Cool and Serve
Let it rest for a few minutes after baking. Garnish with fresh parsley or basil if desired, then serve warm.
Tips
Use thawed frozen peas – If using frozen peas, be sure to thaw and drain them to prevent excess moisture in the casserole.
Avoid overcooking the tuna – Since canned tuna is already cooked, just mix it in and heat it through. Overbaking may dry it out.
Drain all ingredients well – This includes tuna, cauliflower rice, and peas. Removing moisture helps avoid a soggy texture.
Pre-chop and prep – To save time, prep all vegetables and ingredients before you start cooking.
Make it ahead – You can assemble the casserole a day in advance and bake it when you’re ready to eat.
Let it rest after baking – Letting the casserole sit for 5 minutes helps it firm up and makes serving cleaner and easier.
Variations
Add heat – Mix in a pinch of chili flakes or a splash of hot sauce for a spicier version.
Use different cheese – Try goat cheese, feta, or a blend of mozzarella and cheddar for a new flavor profile.
Swap protein – Use shredded chicken, salmon, or even canned mackerel instead of tuna.
Add herbs – Fresh dill, basil, or thyme complement the Mediterranean flavors well.
Include more veggies – Mushrooms, artichoke hearts, or zucchini can be added for extra nutrients and volume.
Top with crunch – Sprinkle with crushed pork rinds or keto breadcrumbs before baking for a crispy topping.
Q&A
Can I use fresh tuna instead of canned?
Yes, you can use cooked fresh tuna. Just flake it into bite-sized pieces before mixing it in.
Are peas keto-friendly?
Peas are slightly higher in carbs than some vegetables, but in moderate amounts (like 1/2 cup in this recipe), they fit well into most keto plans.
Can I make this casserole dairy-free?
Yes, use dairy-free alternatives like coconut cream, vegan cream cheese, and dairy-free shredded cheese.
Can I freeze the casserole?
Yes. Assemble it in a freezer-safe dish (unbaked), wrap tightly, and freeze for up to 3 months. Thaw in the fridge overnight and bake when ready.
What can I serve with this casserole?
It’s complete on its own, but pairs nicely with a green side salad, grilled zucchini, or roasted asparagus.
Nutrition (Approximate per serving, serves 4)
Calories: 400
Protein: 28g
Carbohydrates: 12g
Fiber: 5g
Net Carbs: 7g
Fat: 29g
Saturated Fat: 8g
Cholesterol: 70mg
Sodium: 610mg
Vitamin A: 25% DV
Vitamin C: 30% DV
Calcium: 25% DV
Iron: 12% DV
Note: Peas slightly increase the carb count but add color, texture, and micronutrients.
Conclusion
The Mediterranean Keto Tuna Casserole with Peas is a rich and wholesome dish that brings together classic comfort food and Mediterranean flair in a low-carb format. It’s creamy, flavorful, and packed with nutritious ingredients like tuna, cauliflower, spinach, and peas—all baked into a bubbly casserole that satisfies without weighing you down. Perfect for busy weeknights, meal prepping, or feeding a crowd, this dish is a go-to for anyone eating low-carb but craving something hearty and comforting.