Cheesy Baked Zucchini Casserole {Keto}
This creamy, cheesy Baked Zucchini Casserole is made with fresh zucchini, rich cream, and lots of cheese! It is an easy keto zucchini recipe that everyone will love.
This simple baked zucchini casserole recipe is a great recipe for using up all of that amazing summer zucchini. I love this recipe because it is made with just a few simple ingredients so the flavor of the fresh zucchini isn’t lost and it’s also keto!
That’s right, this Cheesy Zucchini Casserole is a gluten free, keto, side dish that everyone in my family loves. It’s fresh zucchini covered in a rich, creamy cheese sauce made with Gruyere cheese, and perfectly melted Parmesan cheese on top. What’s not to like?
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What You Will Need to Make Cheesy Baked Zucchini Casserole:
- Zucchini – Grow your own, pick it up at the local farmer’s market, or grab some at the grocery store. If you want a little variety, you can mix in some yellow squash too. For this recipe buy the thickest zucchini you can so you get nice, big, round slices to layer into your casserole.
- Onion – This adds a little more flavor to the dish, and onion goes so well with the slightly nutty flavor of the Gruyere cheese.
- Garlic – No recipe is complete without a little garlic. Mixed with the onions it adds just the right amount of flavor.
- Heavy Cream – This makes the cheese sauce thick, creamy, and totally amazing. You can find it in the diary section of the grocery near the milk. Sometimes it is referred to as heavy whipping cream.
- Cheese – For this recipe, you’ll use Gruyere cheese and Parmesan cheese. If you can’t find Gruyere, you can substitute Swiss cheese, and of course, you can always substitute low-fat or nonfat cheese if you prefer.
How to Make Cheesy Baked Zucchini Casserole:
- In a baking dish place the prepared zucchini slices in rows one on top of another until the dish is filled. Set dish aside.
- In a skillet over medium-high heat saute the diced onions with the butter, cooking them until they begin to soften.
- Add minced garlic and continue cooking for 2 minute to slightly soften it.
- Pour the heavy cream into the pan stirring until it begins to bubble.
- Add the Parmesan cheese and Gruyere cheese to the heavy cream, onions, and garlic. Stir together until the cheese melts.
- Pour the cheese sauce over the zucchini spreading it evenly over the zucchini.
- Cover the casserole dish with foil and place in the oven and bake at 450 degrees F for 15 minutes. Then remove the foil, top with the remaining Gruyere and Parmesan cheese and bake for 5 minutes more or until the cheese is melted and bubbling and the zucchini is tender.
- Remove from oven and serve.
How Thick Should the Zucchini Slices Be?
Since we want the zucchini to bake until all of that delicious cheese is melted you want to slice the zucchini into 1/4 inch thick pieces. Making the slices this thick means that the zucchini won’t turn into mush as it bakes. The thicker zucchini slices can withstand the longer cooking time and come out of the oven cooked through but still al dente.
How to Keep Your Zucchini Casserole from Being Watery
Zucchini has a lot of water in it. That means that when it bakes it can release a lot of excess water making your baked zucchini come out watery. So when you’re preparing the zucchini for your casserole you want to make sure to remove as much of that water from it as possible before baking.
It’s a simple process but it does take a little extra time. I promise you though, in the end it’s totally worth it.
After cutting your zucchini lightly salt it on both sides. Then play the slices on a thick layer of paper towels. Let the slices sit for 15 minutes, then flip them over and let them rest for another 15 minutes. You’ll see how much water comes out of the zucchini and is absorbed by the paper towel!
Looking for More Easy Zucchini Recipes?
- Refrigerator Zucchini Pickles
- Chicken Alfredo Zucchini Lasagna
- Zucchini Soup
- Crispy Fried Zucchini
- Zucchini Pad Thai
- One Pot Low Carb Shrimp Alfredo
- One Pot Summer Vegetable Pasta
- Ratatouille
- Spiralizer Recipes
- Summer Zucchini Recipes
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Cheesy Baked Zucchini Casserole
Ingredients
- 40 ounces (approximately) Zucchini, large, sliced 1/4 inch thick
- 1 teaspoon Salt
- 2 tablespoons Butter
- 5 ounces Onion, diced
- 2 cloves Garlic, minced
- ½ cup Heavy Cream
- 6 ounces Gruyere Cheese, grated and divided
- 4 ounces Parmesan Cheese, grated and divided
Instructions
- Preheat oven to 450 degrees F.
- Prepare zucchini by slicing it and then lightly salting it on both sides. Place the salted zucchini slices on a layer of paper towels and let sit for 15 minutes before flipping and letting sit for another 15 minutes. This will remove the excess water from the zucchini before baking.
- In a baking dish place the prepared zucchini slices in rows one on top of another until the dish is filled. Set dish aside.
- In a large skillet, melt butter over medium heat.
- Add onion to the skillet and cook for 2-3 minutes until it begins to soften. Then add garlic and cook for 2 minutes more.
- Pour the heavy cream into the pan stirring until it begins to bubble.
- Add 2 ounces of Parmesan cheese and 4 ounces of Gruyere cheese to the heavy cream, onions, and garlic. Stir together until the cheese melts.
- Pour the cheese sauce over the zucchini spreading it evenly over the zucchini.
- Cover the casserole dish with foil and place in the oven and bake at 450 degrees F for 15 minutes. Then remove the foil, top with the remaining Gruyere and Parmesan cheese and bake for 5 minutes more or until the cheese is melted and bubbling and the zucchini is tender.
- Remove from oven and serve.
Nutrition
How many zucchini’s is 40oz ? What size casserole dish did you use ?
Hi Lucy, we used a 11×7 inch casserole dish. It’s hard to say how many zucchini it takes to get to 40 ounces because they can vary in size so much. It’s best to weigh them out when purchasing so you make sure you have enough.
Anybody ever try adding bread crumbs?
That would be delicious!
Great recipe ! I added about a teaspoon of cayenne to the sauce and used coconut cream instead of heavy cream. It tastes great.
I want to point out that the recipe says cook time is 35 minutes. But you cover it with foil for 15 and then you said to cook it 5 more minutes until tender. I think you meant 25. So I put it back in the oven for another 25 :o)
So glad you liked it and I love the addition of some spice! We actually only cooked ours 20 mins. The addition 15 was the cooking time for the cheese sauce. But cook time can definitely cart depending on the thickness of the zucchini.
Hi! I’m from South Dakota. This recipe is awesome! made it the first time with zucchini, and yellow summer squash, but have also made it with asparagus. Used the swiss and parmesan cheese, and actually doubled the sauce part of it (cheese & cream) personal preference. This will be a big time repeat favorite! Thank You!
Can I freeze it?
You can freeze it but it will have more liquid when you reheat it which may affect the texture.
Delicious and easy! I especially liked the idea of setting the zucchini slices up on the side as it makes a nice presentation as well as keeping some texture to the final product.
Amazing recipe. Did w Leek instead of onion Superb!
Love that idea!