Keto Zucchini Casserole (Easy and Cheesy Recipe) 🥘

Name: Keto Zucchini Casserole
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Ingredients: 3 medium zucchinis (sliced in ¼-inch thick slices); ½ teaspoon sea salt; 2 tablespoons butter; 1 large onion (diced); 2 cloves garlic (minced); ½ cup heavy cream; ¾ cup Gruyere cheese (grated and divided); ¾ cup Parmesan cheese (grated and divided)

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Introducing our delicious Keto Zucchini Casserole! This low-carb twist on a classic comfort food features zucchini, cheese, and savory seasonings. Whether you're following a keto lifestyle or just love zucchini, this dish will become your favorite.

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Preparation and cooking overview
Chef's note
🥘 Ingredients for this keto zucchini casserole recipe
Ingredient substitutions
Additional ingredients
Cooking tools required
Tools substitute options
How to make Keto Zucchini Casserole: step-by-step guide
Cooking methods
Preparation steps
Cooking instructions
What to serve with keto zucchini casserole?
How to make it healthier?
Time-saving tips
What can I prepare ahead of time?
Storage and reheating instructions
Recipe wrap-up and conclusion
Frequently asked questions
📖 Recipe

Preparation and cooking overview

Did we mention that this Zucchini Casserole Recipe is a breeze to make? All you have to do is bake zucchini slices with a creamy cheese sauce. In 45 minutes, this gourmet meal will be at your dinner table.

Chef's note

Add some Mediterranean twist to your dish by adding sun-dried tomatoes or chopped olives to the cheese sauce. This dish also pairs well with sharp cheddar or crumbled feta, so don't hesitate to experiment!

Prep Time: 15 minutes
Cooking Time: 30 minutes
Total Time: 45 Minutes
Difficulty Level: Easy
Recipe Makes 6 Servings

🥘 Ingredients for this keto zucchini casserole recipe

The ingredients for this Low Carb Casserole are easy to find at any grocery store. Here're what to add to your shopping list:

3 medium zucchinis (sliced in ¼-inch thick slices)
½ teaspoon sea salt
2 tablespoons butter
1 large onion, diced
2 cloves garlic, minced
½ cup heavy cream
¾ cup Gruyere cheese, grated and divided
¾ cup Parmesan cheese, grated and divided

Ingredient substitutions

If you are looking for a change in the ingredients, here are a few options for you:

Butter: Use an equal amount of olive or coconut oil instead of butter. Choose the oil based on your preference.
Fresh garlic: If you don't have fresh garlic, use ¼ teaspoon of garlic powder for this recipe.
Heavy cream: If you don't like heavy cream, replace it with coconut cream.
Parmesan cheese: Use Pecorino Romano instead of Parmesan.
Gruyere cheese: If you can't find Gruyere in your grocery store, replace it with mozzarella cheese. It melts well, too.

Additional ingredients

Here are some optional ingredients to take this cheesy casserole to a new level.

Grilled chicken: If you've got some leftover chicken from your last meal, shred it and layer it on top of the fresh zucchini.
Sautéed mushrooms and bell peppers: You can add more keto-friendly vegetables to this casserole. We suggest bell peppers and mushrooms.
Sun-dried tomatoes: Stir chopped sun-dried tomatoes into the cheese sauce for a tangy twist.
Feta cheese: Sprinkle crumbled feta cheese atop the casserole before the second bake.
Fresh herb: Garnish the casserole with fresh basil or parsley before serving.

Cooking tools required

To make this Keto Zucchini Casserole recipe, you will need the following kitchen tools:

Baking dish
Cast-iron skillet
Paper towels
Foil or parchment paper
Knife
Cutting board
Spoon

Tools substitute options

Cast-iron skillet: If you don't have a cast-iron skillet, use stainless steel or a non-stick pan to sauté your veggies.
Paper towels: If you're running low on paper towels, use a clean kitchen cloth or dish towel to draw moisture from the zucchini.

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

Cooking methods

Simmering
Oven-baking

Preparation steps

Gather all the ingredients and measure them.
Dice the onions and mince the garlic cloves.
Grate the Parmesan and Gruyere cheese.

Cooking instructions

Prepare zucchini slices

Slice the zucchini into thin, ¼-inch pieces. Try to slice them as evenly as possible for uniform cooking.
Sprinkle salt on both sides of your zucchini slices.
Place zucchini slices in a single layer on a paper towel and let them rest for 15 minutes. Then, flip them and let them sit for another 15 minutes on the other side.
Pat them dry to remove the moisture.
Lay the zucchini slices in overlapping rows in a baking dish. Once done, set the dish aside for now.

Zucchini being cut into circular slices.

Prepare the cheese sauce

Melt butter in a cast-iron skillet over medium heat.
Add your diced onion to the skillet and cook for 2-3 minutes until it softens.
Stir in minced garlic and cook for an additional 2 minutes.
Once it's done, pour in the heavy cream and give it a good stir.
Once the mixture begins to simmer, add half of the grated Parmesan and Gruyere. Stir until the cheeses are fully melted, and the sauce is well combined.

Cooking onions with heavy cream in a cast iron skillet.

Bake the casserole

Preheat the oven to 400°F (200°C).
Carefully pour the simmering cheese sauce over the zucchini slices in the baking dish.
Cover the dish with foil, pop it in the oven, and bake for 15 minutes.
After 15 minutes, remove the foil, and sprinkle the remaining Gruyere and Parmesan cheese over the top. Bake for extra 5 minutes or until the cheese is bubbly and golden.
Finally, remove the dish from the oven. Scoop out a portion and serve hot!

Chef's pro tip

Start by cutting the zucchini into even slices for consistent cooking. Then, generously season them with salt and let them sit for 30 minutes. The salt will work its magic, drawing out the extra moisture from the zucchini, which helps prevent your casserole from becoming too soggy.

What to serve with keto zucchini casserole?

For a complete meal, serve the casserole with a low-carb side dish. The options are:

Grilled chicken: A grilled chicken breast and our cheesy casserole dish make a satisfying dinner. This is also a really good dish to serve with the Whole Roasted Chicken.
Keto garlic bread: We love to pair our creamy meal with garlic bread made of almond flour. You can also use our Keto Dinner Rolls to make the homemade version of garlic bread.
Green salad: A crisp salad with a tangy vinaigrette offers a refreshing contrast to the hearty casserole. Plus, it's another way to pack more veggies into your meal!
Grilled salmon or Mahi-Mahi: For a complete meal, we suggest Broiled Salmon or our unique Mahi-Mahi recipe.

How to make it healthier?

Buy organic and fresh zucchini and garlic from your local market.
Add more non-starchy vegetables like bell peppers, spinach, or mushrooms for added fiber and nutrients.

Zucchini and cheese recipe on a baking dish.

Time-saving tips

Leverage kitchen tools: Trade your knife for a mandoline slicer when cutting the zucchini. It's not only quicker but ensures consistently thin slices.
Opt for pre-shredded cheese: Save effort by grabbing pre-shredded Gruyere and Parmesan from the store. Just check the ingredients to ensure there are no added starches.

What can I prepare ahead of time?

Zucchini rounds: Slice and salt your zucchini rounds in advance. Just store them in an airtight container until you're ready for baking.
Cheese sauce: Whip up the creamy cheese sauce beforehand. Allow it to cool to room temperature, then pop it into an airtight container in the fridge. When you're ready to bake, just pour the sauce over your prepared zucchini slices, and you're good to go.

Storage and reheating instructions

Storage instructions

Our baked zucchini casserole is easy to store and reheat.

Fridge: Allow any leftover casserole to cool to room temperature, then transfer it to an airtight container. Alternatively, tightly cover the original baking dish with cling film or aluminum foil. It will stay fresh in the refrigerator for 3-4 days.

Note: Do not freeze your casserole dish; it will lose its texture and flavor.

Storage instructions

Oven: Preheat your oven to 350°F (about 180°C). Place the casserole in an oven-safe dish. Cover with aluminum foil to prevent the top from burning, and bake for 15-20 minutes or until thoroughly warmed.
Microwave: Place a casserole serving onto a microwave-safe dish and cover it with a moist paper towel. Microwave on high for 1-2 minutes or until hot throughout.

Recipe wrap-up and conclusion

This Keto Zucchini Casserole is ideal for a warm, gourmet meal after a tiring day. It's not only quick to prepare but also quite simple! Enjoy it as a standalone main course or a delightful side dish — it complements any meal beautifully.

If you're on the lookout for a healthy casserole recipe, give this one a try. Even if you're a beginner in the kitchen, our easy-to-follow technique guarantees a successful result every time!

Looking for more casserole dishes? Here are some popular ones at CIK:

Frequently asked questions

Sure! If you want to add meat to this recipe, toss grilled chicken strips or cooked ground turkey into the cheese sauce.

Yes, yellow squash has a similar taste and texture to zucchini. It will work well in this recipe.

Sure thing! Divide the sliced zucchini and cheese sauce evenly among individual ramekins and bake them.

If the casserole isn't browning, put it under the broiler for a minute or two. Watch it carefully, though, as it can burn quickly.

No, peeling is not necessary. The skin adds color and nutrients, and it softens during cooking.

We don't recommend freezing the casserole—the texture of the zucchini and sauce changes upon thawing.

📖 Recipe

Keto Zucchini Casserole

This Keto Zucchini Casserole recipe features sliced zucchini baked in a creamy cheese sauce, resulting in a delicious and satisfying low-carb dish.

5 from 1 vote

Print Rate Pin Recipe

Course: Main Course

Cuisine: Western

Keyword: easy, keto casserole, low carb, Zucchini casserole

Prep Time: 15

Cook Time: 30

Total Time: 45

Servings:

Calories: 244kcal

Ingredients

3 medium zucchinis sliced in ¼-inch thick slices
½ teaspoon sea salt
2 tablespoons butter
1 large onion diced
2 cloves garlic minced
½ cup heavy cream
¾ cup Gruyere cheese grated and divided
¾ cup Parmesan cheese grated and divided

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