This easy-to-make zucchini squash casserole is a flavorful combination of tender, tasty summer squash and creamy, cheesy sauce! Top it all off with crunchy Panko breadcrumbs for an incredible veggie side dish everyone loves!
A delicious dish that will remind you just why you love squash season!
Trying to trick yourself (or your kids) into eating more vegetables? Then try this tasty zucchini and squash casserole that non-veggie AND veggie lovers will all love!
Thinly sliced zucchini and yellow squash are mixed with a delicious homemade cheese sauce and then baked to perfection! The mild flavors of the zucchini and squash are covered in a delicious garlic and cheese sauce and sprinkled with the perfect crunchy topping.
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The combination is an amazingly flavor-filled dish that you will forget is mostly veggies! Personally, I could easily eat a hearty serving as my entire dinner!
❤️ Why You'll Love This Recipe!
Super Easy! When you realize how easy it is to make a homemade cheese sauce with some basic kitchen staples, you will want to experiment with using it on lots of other veggies!
So Tasty! This creamy, cheesy sauce is full of flavor and will seriously make you forget you are eating not one, but two different vegetables! It’s so good, your kiddos may just ask for seconds!
It's Versatile! Swap the seasoning, cheese types (just make sure to use a good melting cheese!), or veggies to create a personalized side dish!
🥘 Ingredients
If you don’t already use Italian herbs and Panko breadcrumbs, you’ll love making them new staples in your pantry! Most of the other zucchini squash casserole ingredients are common kitchen staples.
- Zucchini - Zucchini is a green squash that is very versatile. It has a mild flavor and does not have seeds you have to remove, which makes it extremely easy to cook with.
- Yellow Squash – Yellow squash is another summer squash (squash with thin, edible skin). Like zucchini, it has a mild flavor and takes on the flavors its cooked with.
- Butter – Salted butter will give you the best flavor in this recipe, as it is used to create the base for the cheese sauce.
- All-Purpose Flour – AP flour is combined with the butter to make a roux that helps thicken the sauce.
- Garlic – Garlic is a great flavor enhancer with a unique flavor! You can chop up fresh garlic or use the jarred minced garlic.
- Whole Milk – Whole milk is important for this recipe because it provides a little bit of fat that helps thicken the sauce.
- Italian Herbs (Italian Seasoning) – Common Italian herbs are dried basil, dried oregano, dried rosemary, dried thyme, dried marjoram, and sometimes sage. Italian Seasoning is a combination of these herbs and the easiest way to get the best balance of flavors.
- Cheddar Cheese – Grated cheese is best for this recipe, as it will melt the easiest when added to the sauce base.
- Panko Breadcrumbs - These breadcrumbs are used as a topping to add an extra “crunch” to the casserole.
- Salt and Pepper – Begin slowly and taste the sauce as you go.
📖 Variations
Broccoli and cauliflower – Replace the zucchini and yellow squash with broccoli and cauliflower. Rinse the broccoli and cauliflower and cut into individual florets. Follow the same directions to prepare the sauce and bake the casserole as above.
Potatoes – It’s not quite a green vegetable dish, but you can make this into a delicious creamy and cheesy potato side dish! Wash, peel, and cut 6 medium potatoes into 1-inch chunks. Follow the same directions to prepare the sauce and bake the casserole as above.
🧂 Substitutions
Heavy cream or Half & Half: To make a truly indulgent sauce, substitute either heavy cream or half and half for the whole milk.
Gluten Free Sauce: If you are gluten-sensitive you can use corn starch to thicken the sauce instead of the flour.
🔪 Instructions
Follow these super easy instructions to get an amazing veggie dish on the table that the whole family will love!
Make the Sauce
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- Preheat. Set your oven to 375°F (190°C) and lightly butter or grease your cast iron skillet or baking dish.
- Prepare vegetables. Wash 3 each zucchini and yellow squash then slice into rounds about ¼ inch thick. Arrange the zucchini and squash in a cast iron pan or baking dish.
- Sauté the garlic. Next, in a large skillet over medium heat melt 4 tablespoons butter and saute 1 tablespoon of minced garlic for a 1-2 minutes.
- Make the roux. Add ¼ cup flour and whisk into the melted butter and garlic.
- Whisk in the milk. Slowly start adding 2 cups of milk and whisk into the butter and flour mixture. Continue adding the milk while whisking until the mixture is smooth with no lumps.
- Season and melt cheese. Reduce heat and stir in 1 tablespoon of Italian herbs, 2 cups of grated cheese, salt, and pepper (to taste). Whisk or stir until all the cheese has melted. Remove from heat.
Assemble the Casserole
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- Mix sauce with vegetables. Pour the melted cheese mixture over the arranged zucchini and squash. Top with ½ cup of Panko breadcrumbs.
- Bake until golden. Place in the middle of your oven's center rack and cook at 375°F (190°C) for 50 minutes or until the top has browned sufficiently.
- Serve. Remove from the oven and allow to cool slightly before serving.
If serving your zucchini squash casserole alongside another dish, cover with foil when you remove it from the oven and let it sit on top of the oven to keep it warm until you are ready to serve it. Enjoy!
💭 Tips & Notes
Get all the flour combined with the butter first.
- The base of this cheese sauce is a roux that is made from combining butter and flour. It’s important to get all the flour and butter combined, before adding the milk.
- Be sure to cook the roux for 1-2 minutes to cook off the flour flavor (before adding the milk).
Take your time adding the milk!
- To get the sauce as smooth as possible, take your time adding in the milk. I suggest measuring the milk into a an easy to pour cup.
- Slowly pour a little at a time into the pan as you whisk it together with the roux. A whisk is an important kitchen tool to use, as it will help you get a smooth sauce.
🥡 Storing & Reheating
Simply cover your dish with a lid or plastic wrap, or transfer it to an airtight storage container, to save any leftovers.
Your leftovers can be refrigerated for up to 3-4 days in the refrigerator. I find, however, that the veggies are best if enjoyed with 1-2 days.
Reheating Zucchini Squash Casserole
Your veggie casserole is best reheated in the oven. I even like to add some extra Panko breadcrumbs on top to add some more crunch to the leftovers.
🍽️ Serve With
This casserole is the perfect addition to a delicious baked or grilled chicken dish! Try it with one of these easy and delicious chicken recipes!
- Baked BBQ Chicken Breast
- Instant Pot Chicken Thighs
- Baked Chicken Quarters
- Shake and Bake Chicken
- Hasselback Chicken
Do you love a recipe you tried? Please leave a 5-star 🌟rating in the recipe card below and/or a review in the comments section further down the page.
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📖 Recipe Card
Zucchini Squash Casserole
Ingredients
- 3 medium zucchini (sliced into ¼ inch rounds)
- 3 medium yellow squash (sliced into ¼ inch rounds)
- 4 tablespoon butter (½ stick+a little extra to grease the pan)
- ¼ cup all-purpose flour
- 1 tablespoon minced garlic
- 2 cups whole milk
- 1 tablespoon Italian Herbs (or Italian seasoning)
- 2 cups cheddar cheese (grated, or use a cheese blend of your choice)
- ½ cup Panko breadcrumbs
- salt & pepper (to taste)
Instructions
- Preheat your oven to 375°F (190°C) and butter or grease a cast iron skillet or baking dish.
- Wash the zucchini and yellow squash and slice into rounds about ¼ inch thick. Arrange the zucchini and squash in the cast iron pan.3 medium zucchini, 3 medium yellow squash
- Next, in a large skillet over medium heat melt the butter. Add the garlic and saute for a couple of minutes.4 tablespoon butter
- Add the flour and whisk into the melted butter and garlic.¼ cup all-purpose flour, 1 tablespoon minced garlic
- Slowly start adding the milk and whisk into the butter/flour mixture. Continue adding the milk while whisking until the mixture is smooth with no lumps.2 cups whole milk
- Add the Italian herbs, cheese, salt, and pepper. Whisk until all the cheese has melted. Remove from heat.1 tablespoon Italian Herbs, 2 cups cheddar cheese, salt & pepper
- Pour the melted cheese mixture over the arranged zucchini and squash. Top with the Panko.½ cup Panko breadcrumbs
- Bake at 375°F (190°C) for 50 minutes or until the top has browned sufficiently.
- Remove from oven and allow to cool slightly, serve and enjoy!
Notes
- Whole milk is preferred in this recipe, if using 2 % or 1% you may need to increase the flour to thicken the sauce.
Nutrition
Angela is an at home chef that developed a passion for all things cooking and baking at a young age in her Grandma's kitchen. After many years in the food service industry, she now enjoys sharing all of her family favorite recipes and creating tasty dinner and amazing dessert recipes here at Bake It With Love!
Sharon says
only had 2 of zuc and squ so I improvised with a whole onion sliced sliced. I liked it and so did my parents. Also did porkchops in my new air fryer, did a side of jasmine rice and it made a nice meal. Or course we had yummy brownies still warm topped with a scoop of vanilla ice cream. Folks are on salt free diet and it's hard to please them. Their old and have many wonderful meals throughout their travels!!! LOL
Anonymous says
Can you use a casserole dish?
Angela @ BakeItWithLove.com says
Yes, but it would still need to be a smaller casserole dish or one that is close in shape and size to the 12-inch cast iron skillet used here. Enjoy!
Anonymous says
Good and simple instructions to follow.
Thank you
Angela Costa says
Eu adorei....fiz agora pro almoço
"I loved it....I made it now for lunch"
Angela @ BakeItWithLove.com says
Maravilhoso! Estou feliz que você gostou.
"Wonderful! I'm glad you enjoyed it."
Lise says
Excellent recipe, love this sauce, which is similar to Hollindaise.
Only had 3 large squash / zucchini, but left the amount of the sauce the same. It is a little soupier, but that will thicken as it cools. I did cut the Italian Seasoning to 1 1/2 tsp, which is plenty for me. Otherwise, followed recipe as written.
Thank you, so much for sharing your recipe, I will definitely make this again & again, as well as sharing with family & friends.
Sincerely,
Lise
Kimmy says
Tonight it will be my first time to try this it’s in oven right now cross finger I did make one tiny error is flour which it was 1/2cup of flour oh shoot!! And I use 2% milk So far what I see the picture step by step same way what I did. I’m nervous wreck hope it turn tasty!! Just one tiny error. Will that be ok. I did add little more milk less 1/3 of milk
Stephanie says
Can this be made on the stovetop completely
Anonymous says
Makes LOTS so more for Family
Anonymous says
Very good but a little heavy on the Italian seasoning. I’ll make again but reduce the amount I use.