This extremely easy and cheesy baked Zucchini Casserole recipe uses 3 lbs of zucchini, a blend of herbs and spices (for a little heat!), and blended with the perfect amount of shredded cheese to still keep it healthy. It is a quick and easy low-carb and gluten-free baked side dish that works as easily for breakfast as it does dinner. So much flavour from the garlic, herbs, and Parmesan cheese, your entire family will love it!
Need more ideas? Check out my 30 healthy zucchini recipes or 40 healthy spaghetti squash recipes – from dinner to dessert, squash can save any meal!
Table of contents
Zucchini Casserole
I don’t think you can ever give a really good casserole too much credit. It’s quick, easy, and total comfort food. It’s great for serving a crowd because there is a lot of it, and thanks to the cheesy goodness it’s totally kid-friendly as well. Just wait until they start asking for seconds on zucchini!
I also don’t think you can give the versatile zucchini too much credit because it really is a jack of all trades! I’ve used zucchini 101 different ways it feels like, and I never get sick of it. For example my crustless zucchini quiche, stuffed zucchini boats, baked zucchini fritters, and a zucchini potato bake.
You can also hide it in tons of desserts too. Just try these zucchini brownies, lemon zucchini muffins, chocolate zucchini bread, or zucchini banana bread! You can’t even taste the zucchini!
Then there’s the cheese…I mean, come on. It’s cheese! So when I came up with this incredibly easy zucchini casserole recipe that had the comforts of a classic casserole, the flavours of zucchini, herbs, and spices, all blended and baked with just the right amount of gooey cheese, I knew it was a winner.
This recipe doesn’t require an obscene amount of cheese to make it cheesy. Otherwise, we might have a harder time claiming it was healthy. Make no mistake, it is healthy and full of flavour and perfect as a light lunch, a side dish for dinner, or a fantastic addition to your brunch menu!
Most of us can relate to needing new zucchini recipes with all of the zucchini we’ve got throughout July-August. This little (or in some cases gigantic) squash is deceiving. One small plant grows so big and produces a crazy amount of zucchini. It’s no wonder we have an abundance.
This zucchini casserole recipe calls for 3 lbs of garden zucchini that you can put to use. Yes, you read that right, 3 lbs!
Now, you’ve only got 33 lbs more to use up 😉
Why This Zucchini Casserole Recipe Works?
- A healthy casserole dish whose main ingredient is a vegetable (yes, we’re calling it a vegetable).
- Cost-effective way to feed a crowd, especially if you grow your own zucchini!
- Loads of flavours that everyone will love.
- It’s super simple to make and is great for easy weekends and rushed weeknights.
- A vegetarian side dish or main dish that can quickly be made with meat if preferred.
Is Zucchini Healthy?
In a nutshell, yup!
- Vitamin A – improves eye health.
- Vitamin C – boosts the immune system and guards against asthma.
- Fiber – lowers cholesterol.
- And potassium – lowers blood pressure.
Ingredients for Baked Zucchini Casserole
You won’t find any unnecessary ingredients in this casserole. No breadcrumbs, heavy cream, flour, or even more terrifying Bisquick. Just simple veggies, herbs, and a bit of cheese!
- Chopped zucchini or squash: If I can, I prefer to chop vs. grate anything. It saves so much time and I like the heartier texture much better. Cut the zucchini into about 1-inch pieces. It is enough to bake small pieces of zucchini to end up with the best casserole.
- Aromatics: Good old finely chopped onion and minced garlic are always a welcome duo in any casserole.
- Eggs: 2 eggs in the recipe are to help smooth and bind all ingredients. If you have an allergy or simply do not have any on hand, feel free to skip eggs.
- Herbs and spices: Basil, oregano, salt & pepper, red pepper flakes. A simple blend of seasoning that adds freshness as well as a little heat. Salt and pepper are always a good way to round out the flavours of any dish.
- Cheese: As for other cheese besides Parmesan, I used smoked Gouda. Any hard cheese with a strong flavour profile is great. For example, Gruyere, Havarti, old aged cheddar, Tex Mex. This way, you will use less but still get maximum flavour. We will not be using 3-4 cups of cheese because, frankly it defeats the purpose of eating more zucchini.
Squash vs. Zucchini? In North America, we have yellow and green zucchini. All zucchini are squash, but not all squash are zucchini. So, both yellow and green zucchini squash can be used in this recipe. Why not a combination of both!
How to Make Zucchini and Squash Casserole
How to Drain Excess Water from Zucchini
Before you begin: Zucchini is made of 90% water. If not more. Which is perfect for a casserole to make it moist without the extra calories. However, there is such a thing as too much moisture, so we need to get rid of it. Easy-peasy. This is the same way we do it when baking zucchini into this almond flour zucchini bread (air fryer method) too.
Squeezing Zucchini
- Colander: Place chopped zucchini in a colander lined with a kitchen towel.
- Salt: Sprinkle with 3/4 teaspoon salt and toss with your hands.
- Rest: Let sit for 10 minutes.
- Squeeze: Squeeze in a towel over the sink for a few minutes. At first, there won’t seem much liquid but keep twisting at the top of the towel, turning and squeezing the ball.
Assemble Zucchini and Squash Casserole
- Whisk eggs with spices: Whisk eggs in a bowl. Add garlic, onion, spices, and 1/2 amount of cheese.
- Add squash: Then toss squeezed zucchini in the mixture and transfer to sprayed baking dish.
- Bake uncovered for 25 minutes in preheated oven at 375 degrees F. You do not want to bake zucchini casserole covered because it will be extra watery and unappealing.
Tip: I used an abundance of young onions this time. That’s why you see green in the photos.
Optional Add-In’s and Variations
- If you do like the added crunch of a breaded topping, go ahead and add that on top. A combination of parmesan, melted butter and seasoned homemade breadcrumbs would be an awesome way to top it off. You can opt for gluten-free as well if that’s what you prefer.
- If you prefer shredded, do that. As mentioned earlier, I would rather dice my zucchini as opposed to shredding, but if you like the texture of it shredded, by all means, go ahead.
- Cut zucchini into 1″ rounds and place them in the baking dish in rows, overlapping just slightly so it all fits. Just another way to cut the zucchini for this zucchini and squash casserole.
- For added veggie options, think about Roma tomatoes (not too watery), mushrooms, eggplant, or a combination of a variety of other squash would be great.
- Up the protein: Leftover shredded chicken or diced turkey would be yummy!
Tips for Best Results
- I can’t stress enough the importance of draining the zucchini first.
- No need to peel zucchini. The skin is thin, delicate, and completely edible. In fact, it comes with loads of extra nutrients, so save yourself some time and effort and keep the skin on.
- Best enjoyed immediately once out of the oven.
- To make this a complete meal, serve with a protein (see below), and perhaps some brown rice or quinoa too!
FAQs
A couple of things to keep in mind when making this zucchini and squash casserole is to drain as much of the excess water that comes in zucchini (it’s a lot!). The salt used will help draw out the water, and allowing it to sit over a colander will provide a way for the water to drain so the zucchini isn’t sitting in it. Then, squeezing the remaining liquid helps too.
Also, you want to bake it uncovered that way there is no steam captured creating condensation making the casserole mushy.
In very easy, non-scientific terms, the process of osmosis is when a solvent (in this case water) naturally moves from an area where there is a high concentration of water (the zucchini) to an area of low concentration (the salt) through what is called a semi-permeable membrane (the skin of the zucchini). This is a naturally occurring process that you may have learned about in science class.
Don’t worry, no pop quizzes today!
No need. Not only does the skin of the zucchini help to hold the structure of the soft vegetable, but it’s also thin and delicate enough that it is easily digestible. It’s highly nutritious and it is barely noticeable especially when cooked.
Sure you can! As mentioned above, Roma tomatoes are great for this as they do not hold as much water as other types, so they won’t add too much moisture. This is a good thing otherwise our whole draining excess water from the zucchini thing would have been for nothing!
Yes, it is! If you don’t add any breadcrumb to yours, this zucchini and squash casserole is completely gluten-free and low carb!
Serving Recommendations
Let’s be honest, this low-carb baked zucchini casserole recipe will not keep anyone full for longer than 1 hour. We need to bulk up the meal with additional protein.
My recommendations would be:
Making Baked Zucchini Casserole in Advance
Make ahead: You can prepare zucchini casserole up to 1 day ahead. Refrigerate assembled and covered. Do not forget to uncover before baking. If you see some accumulated liquid at the bottom of the baking dish it is OK.
Do not freeze: You cannot freeze zucchini casserole. Not before and not after baking. The water content is just too high, even after draining.
More Zucchini Recipes
I do love a good healthy zucchini casserole. Even a more time-consuming one is so much fun to make with a glass of wine. Eating all those vegetables makes wine + cheese almost guilt-free.
- Zucchini tomato bake
- Zucchini lasagna
- Chicken zucchini casserole
- Zucchini quiche
- Low carb parmesan zucchini sticks
- Sautéed zucchini
- Chicken, zucchini, and corn
Or feel free to browse through my entire list of all zucchini recipes!
Hope you enjoy this zucchini casserole. I would love to hear how you liked it in the comments below. My kids gave it 5 stars. Would you?
Zucchini Casserole {Low Carb & Gluten Free}
Ingredients
- 3 lbs zucchini chopped into 1″ pieces
- 1 small onion finely chopped
- 2 garlic cloves minced
- 2 large eggs
- 1 tbsp olive oil extra virgin
- 1 tsp basil dried
- 1 tsp oregano dried
- 3/4 tsp salt
- Ground black pepper to taste
- Pinch of red pepper flakes
- 3/4 cup Gouda Gruyere or Tex Mex cheese, shredded
- 1/3 cup Parmesan cheese grated
- Cooking spray
Instructions
- Preheat oven to 375 degrees F and spray large 9 x 13 baking dish with cooking spray.
- Place chopped zucchini in a colander lined with kitchen towel and sprinkle with salt. Toss with your hands and let sit for 10 minutes.
- In the meanwhile, in a large bowl whisk the eggs. Add onion, garlic, olive oil, basil, oregano, pepper, red pepper flakes and 1/2 amount of both cheeses. Whisk.
- Squeeze zucchini in a towel over the sink for a few minutes. At first there won’t seem much liquid but keep twisting at the top of the towel, turning and squeezing the ball.
- Add squeezed zucchini to the bowl with mixture, stir to coat and transfer to previously prepared baking dish. Sprinkle with remaining 1/2 of both cheeses.
- Bake uncovered for 25 minutes. Remove from the oven and serve warm or cold.
Store: Refrigerate covered for up to 3 days.
Make Ahead: You can prepare zucchini casserole for up to 1 day ahead. Refrigerate assembled and covered. Do not forget to uncover before baking. If you see some accumulated liquid at the bottom of the baking dish it is OK.
Do not freeze. Not before, not after baking.
Notes
- As for other cheese besides Parmesan. I used smoked Gouda. Any hard cheese with strong flavor profile is great. For example, Gruyere, havarti, old aged cheddar, Tex Mex. This way you will use less of cheese.
- I used an abundance of young onions this time. That’s why you see green.
- You do not want bake zucchini casserole covered because it will be extra watery and unappealing.
Nutrition
Recipes and images are a copyright of ifoodreal.com. It is against the law to republish recipes anywhere including social media, print and all world wide web. Nutritional info is provided for informational purposes only and to the best knowledge.
Not bad, pretty easy to make. Next time will use a little more garlic to my taste. A good recipe to use the zucchini bounty!
This recipe was easy to make and tasted good.
Thanks for sharing Tamara!
Very good, enjoyed be all. I did add grape tomatoes for color.
That’s great Sandy!
Loved this. It was a huge hit in my home. I added breadcrumbs on top for a little more texture. Yum.
Nice addition with the breadcrumbs. Thanks for sharing Tanja!
Took this dish to a potluck, never having made it before…..it was a huge hit! Thank you, I’ll be making it again!
Awesome. So happy to hear this.
Olena thank you for posting this amazing casserole. I used 1/2 Zucchini and 1/2 Yellow squash. The flavor balance is spot on. My family loved it!!!
I am so happy to hear this Kelly!
This is the best zucchini casserole I’ve come across! The cubes make all the difference, no more mushy wet shreds! I was heavy handed with seasoning and it was just to my family’s taste. My son took the leftovers home and asked me for the recipe. Thanks for this great recipe. I’ll be making it often.
Thanks for sharing! I love hearing that my recipe was enjoyed!
I have a question: To remove the water from the zucchini you have listed to use 1 teaspoon of salt and in the ingredients list you have 3/4 teaspoon of salt. Is it 1tsp. for the water removal and 3/4tsp to be used the recipe?
3/4 tsp total to remove water and no more added after. I will fix and clarify it in the recipe. Thanks for asking!
Thank you for your delicious recipe. I cut the recipe in half and still had a lot! I added cooked Italian Sausage that I’d drained and patted dry on paper towels. So yummy, thank you!
You are very welcome Norma!
Very good recipe, my cholesterol is a bit high so I went low in cheese. I love the recipe and will make it again.
Can you reheat in microwave? I cook meals for my Mom who is 88 and only reheats in microwave or tiny crock pot. I’d like to add a protein, like cooked chicken breast and put small portions in a microwave-safe dish for her to reheat. Thanks.
Of course!
Sunday morning brunch, excellent dish!! Thank you for sharing ♥️
Fantastic use of the dish! Glad you enjoyed the recipe, Ari!
Delicious
So happy to hear you loved this recipe, Kathy!
We loved this one! Made it a few times 🙂 the last time I made it I added cherry tomatoe’s halved. So delicious!!! Thanks for sharing!
Fantastic! Glad you enjoyed the recipe, Barb!
The instructions say to use 1/2 amount of both cheeses in step 3. What do you do with the other half?
Sprinkle it on top before baking. Sorry missed that. Will fix.
Love this recipe. Simple and quick to make. The flavour combined with the cheese is amazing.
I didn’t have the cheese recommended so I used pepper jack cheese which I had.
Thanks Olena.
That’s a flavorful cheese you used. Perfect!