Name: Keto Tuna Zoodle Casserole Recipe
Prep time: 15 min
Cook time: 25 min
Total time: 40 min
Cuisine: American
Ingredients: 4 medium zucchini, spiralized; 2 cans (5 ounces each) tuna in water, drained; 8 ounces mushrooms, sliced; 2 cloves garlic, minced; 2 tablespoons butter; 4 ounces cream cheese, softened; ½ cup heavy cream; ½ cup chicken broth; 1 cup shredded cheddar cheese; ½ cup shredded mozzarella cheese; ¼ cup grated Parmesan cheese; ½ teaspoon onion powder; ½ teaspoon dried thyme; ½ teaspoon salt; ¼ teaspoon black pepper

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If you’re craving a comforting, homey dish without the carb overload, the Keto Tuna Zoodle Casserole Recipe is an absolute game changer. Imagine tender zucchini noodles mingling with flaky tuna and earthy mushrooms, all brought together by a luxuriously creamy, cheesy sauce that bakes into a bubbling golden masterpiece. This dish is not only bursting with flavor but also keeps things light and keto-friendly, making it perfect for anyone looking to nourish their body without sacrificing taste. Whether you’re juggling weeknight dinners or entertaining guests who love wholesome food, this casserole will quickly become a favorite in your kitchen.

Ingredients You’ll Need

The image shows a white marbled surface with fresh ingredients neatly arranged. There are three whole green zucchinis placed vertically on the right side. Below them, a small white bowl holds chopped pickles with a greenish hue. Beside it, a small clear bowl contains yellow seasoning. A metal measuring spoon filled with white salt is placed nearby. On the left, a measuring cup filled with a creamy white sauce sits next to three celery stalks tied together with a white string and a few green chives on top. Two small shallots, light purple and brown, are positioned on the far left. An open tin of light brown tuna is located in the upper left corner, with a glass of milk just behind it. All items appear fresh and natural. Photo taken with an iphone --ar 4:5 --v 7

Gathering your ingredients for this recipe is delightfully simple, yet each one plays a critical role in building the dish’s inviting texture, rich flavor, and gorgeous appearance. These essentials are easy to find and come together beautifully to create that perfect balance of creamy, cheesy, and fresh.

4 medium zucchini, spiralized: The star low-carb substitute for traditional noodles, providing a fresh crunch and beautiful color.
2 cans (5 ounces each) tuna in water, drained: Offers flaky, meaty protein that’s mild but satisfying.
8 ounces mushrooms, sliced: Adds earthiness and a meaty texture to round out the dish.
2 tablespoons butter: For sautéing mushrooms and adding richness.
2 cloves garlic, minced: Gives a fragrant depth that brightens the casserole.
4 ounces cream cheese, softened: Creates a luscious cream base that thickens the sauce beautifully.
½ cup heavy cream: Brings a velvety silkiness for that indulgent mouthfeel.
½ cup chicken broth: Balances richness with a subtle savory note.
1 cup shredded cheddar cheese: Adds sharp, tangy flavor and melty goodness.
½ cup shredded mozzarella cheese: Topping ingredient that melts and browns perfectly.
½ teaspoon onion powder: Enhances depth with a mild onion essence.
½ teaspoon dried thyme: Provides a gentle herbal lift that harmonizes all flavors.
½ teaspoon salt: Essential seasoning to bring everything together.
¼ teaspoon black pepper: Adds just the right amount of heat.
¼ cup grated Parmesan cheese: For a nutty, savory topping that crisps up wonderfully.

How to Make Keto Tuna Zoodle Casserole Recipe

Step 1: Preheat and Prepare

Start by preheating your oven to 375°F (190°C) and lightly greasing a 9×13-inch baking dish. This base is where all the magic will come together, so a good non-stick layer will help when it’s time to serve.

Step 2: Drain and Dry the Zoodles

Place your spiralized zucchini noodles in a colander and sprinkle them lightly with salt. Let them rest for 10 minutes—this step is crucial to draw out excess moisture. After, wring them gently with paper towels to avoid a watery casserole, while keeping the noodles tender.

Step 3: Sauté Mushrooms and Garlic

Melt butter in a large skillet over medium heat, then add the sliced mushrooms. Cook until they’re softened and lightly browned—about 5 to 6 minutes. Toss in the minced garlic and cook for an additional 30 seconds to infuse the mixture with aromatic flavor.

Step 4: Create the Creamy Sauce

Reduce the heat to low and stir in the softened cream cheese, heavy cream, and chicken broth. Keep stirring until the cream cheese completely melts and the sauce becomes silky smooth and rich.

Step 5: Season and Melt in Cheese

Add the shredded cheddar cheese, onion powder, dried thyme, salt, and black pepper. Cook gently until the cheese melts into the sauce, creating a creamy, savory mixture that will coat every bite.

Step 6: Combine Tuna and Zoodles

Gently fold the drained tuna and the prepared zucchini noodles into the cheese sauce, ensuring everything is evenly coated without breaking up the tender tuna too much.

Step 7: Bake to Perfection

Transfer the mixture to your prepared baking dish. Sprinkle the shredded mozzarella and grated Parmesan evenly over the top. Bake for 20 to 25 minutes until the casserole is hot, bubbly, and the cheese topping turns a lovely golden brown.

Step 8: Rest Before Serving

Let the casserole rest for 5 minutes once it’s out of the oven. This helps the flavors meld and makes serving easier as it sets slightly.

How to Serve Keto Tuna Zoodle Casserole Recipe

A white pan filled with a creamy, mixed dish that has a top layer of browned melted cheese in light golden-brown spots. Below the melted cheese, there are layers of soft white and light green cabbage pieces with some green peas spread throughout. The creamy sauce beneath looks smooth and thick, coating the vegetables and small chunks of light white meat evenly. A silver spoon is scooping a portion from the pan showing all the layers together with the creamy white sauce glistening. The background is a white marbled surface photo taken with an iphone --ar 4:5 --v 7

Garnishes

A sprinkle of freshly chopped parsley or dill right before serving adds a pop of color and freshness that contrasts beautifully with the creamy casserole.

Side Dishes

Pair this casserole with a light green salad dressed in lemon vinaigrette or some steamed asparagus for a well-rounded keto meal that keeps the carb count low but satisfaction high.

Creative Ways to Present

For a fun twist, serve this casserole in individual ramekins for a personal touch at dinner parties. You can also top each portion with a dollop of sour cream or a squeeze of fresh lemon juice to brighten the deep, cheesy flavors.

Make Ahead and Storage

Storing Leftovers

To keep your leftovers fresh, store them in an airtight container in the refrigerator for up to 3 days. This casserole reheats beautifully without losing its creamy texture.

Freezing

If you want to save portions for later, this dish freezes well. After baking, cool completely, cover tightly, and freeze for up to 2 months. Thaw overnight in the fridge before reheating.

Reheating

Reheat leftovers in the oven at 350°F (175°C) for about 15 minutes or until warmed through. Alternatively, microwave individual servings until hot, stirring halfway through for even heating.

FAQs

Can I use canned salmon instead of tuna?

Absolutely! Canned salmon works wonderfully in this recipe and offers a slightly richer, more distinct flavor that pairs beautifully with the creamy sauce and zoodles.

Is it okay to use frozen mushrooms?

While fresh mushrooms are best for texture and flavor, frozen mushrooms can be used in a pinch. Just be sure to thaw and drain them well to avoid excess moisture.

How do I prevent zucchini noodles from becoming mushy?

Salting and draining your zoodles before cooking is key. This draws out moisture and helps keep them firm enough to withstand baking without turning soggy.

Can I make this dish dairy-free?

You can try substituting dairy with non-dairy cream cheese and cheese alternatives, but the texture and flavor will be different. Using coconut cream or cashew cream can help mimic the richness.

What is the best way to spiralize zucchini?

A handheld spiralizer or an electric model both work well. Choose medium-sized zucchinis for sturdy noodles that hold their shape during cooking.

Final Thoughts

This Keto Tuna Zoodle Casserole Recipe is a true pantry hero that combines comfort and creativity in every bite. It’s a deliciously simple way to enjoy classic flavors while keeping your meals light and keto-friendly. I promise once you try this casserole, it will earn a permanent spot on your dinner rotation. Go ahead, dive in and savor the magic of zoodles and tuna in this creamy, cheesy delight!