Classic Southern Zucchini Casserole

Growing up in a family that loved vegetables, zucchini was always a staple at our dinner table. But let’s be honest – plain steamed zucchini can get a bit boring after a while. That’s why this southern zucchini casserole has become my go-to side dish when I want something comforting and easy to make.

I often prep this casserole while I’m already in the kitchen making other things. It’s one of those dishes that just makes sense – combining fresh zucchini with cheese and a few pantry staples creates something that even my veggie-skeptical kids will eat. Plus, it’s perfect for those summer months when gardens and farmers’ markets are overflowing with zucchini.

You know what’s really great about this recipe? You can assemble it ahead of time and pop it in the oven when you need it. Whether it’s for a weeknight dinner or a neighborhood potluck, this casserole never disappoints. And if you’re wondering what to do with all those summer zucchini, well, I’ve got you covered.

What Kind of Zucchini Should I Use?

For this casserole, medium-sized zucchini between 6-8 inches long are your best bet. These younger, smaller zucchini are more tender and have smaller seeds than their larger counterparts, which can get watery and bitter. When shopping, look for zucchini that feels firm and heavy for its size, with smooth, slightly glossy dark green skin. If you can only find larger zucchini, no worries – just cut out the seedy center before slicing, as this part tends to make your casserole too wet. Fresh from the garden or farmers market is great, but grocery store zucchini works perfectly fine too.

Options for Substitutions

This casserole recipe is pretty adaptable and here are some easy swaps you can try:

• Yellow squash and zucchini: You can use all zucchini or all yellow squash if you prefer. Other summer squash varieties work well too. Just keep the total amount of squash the same at 4 cups.
• Mayonnaise: Not a mayo fan? Try Greek yogurt or sour cream instead. These will give you that same creamy texture, though the taste will be a bit tangier.
• Chicken stock: Vegetable stock works just as well, or you can use water with a bit of extra seasoning if you’re in a pinch.
• Panko breadcrumbs: Regular breadcrumbs or crushed crackers make good alternatives. You can even use crushed pork rinds for a low-carb option.
• Parmesan cheese: Romano or Pecorino cheese can step in for Parmesan. Even sharp cheddar works well if that’s what you have on hand.
• Italian seasoning: If you don’t have the blend, use a mix of dried basil, oregano, and thyme – about 2/3 teaspoon of each.

Watch Out for These Mistakes While Cooking

The biggest challenge when making zucchini casserole is dealing with excess moisture – cutting your squash too thick or not removing enough water can leave you with a soupy dish instead of a creamy casserole. To prevent this, slice your zucchini and yellow squash into uniform 1/4-inch pieces, then lay them on paper towels and sprinkle with salt for 15 minutes to draw out extra moisture. Another common mistake is undercooking the vegetables before adding the topping, which can result in a crunchy, undercooked texture – make sure to bake until the squash is tender but not mushy, usually about 20-25 minutes. For the crispiest topping, avoid pressing the breadcrumb mixture down into the casserole; instead, sprinkle it evenly over the top and let it form a golden-brown crust under the broiler for the final 2-3 minutes of cooking (but keep a close eye on it to prevent burning).

What to Serve With Zucchini Casserole?

This cheesy zucchini casserole makes a fantastic side dish, but it can also shine as a main course with the right accompaniments. For a complete meal, try serving it alongside some grilled chicken breast or baked fish – the creamy, garlicky flavors work really well with simple proteins. If you’re keeping things vegetarian, a scoop of fluffy rice or quinoa helps soak up all that tasty sauce. I also like to add a fresh element to the plate with a simple tomato salad or some crusty bread for extra satisfaction. When serving this as a side dish, it pairs perfectly with classic Southern main courses like fried chicken, meatloaf, or grilled pork chops.

Storage Instructions

Keep Fresh: This zucchini casserole stays good in the fridge for up to 4 days when stored in an airtight container. The panko topping might lose some of its crunch over time, but the flavors actually get better as they meld together!

Freeze: While you can freeze this casserole, the zucchini might release extra water when thawed, making it a bit watery. If you decide to freeze it, use a freezer-safe container and it’ll keep for up to 2 months. Just know the texture won’t be quite the same as when it’s fresh.

Reheat: To warm up leftovers, pop them in the oven at 350°F for about 15-20 minutes, or until heated through. If you’re in a hurry, the microwave works too – just heat in 30-second intervals. To bring back some crunch, you can sprinkle on fresh panko before reheating.

Make Ahead: You can prep this casserole up to a day ahead! Just assemble everything except the panko topping, cover, and refrigerate. When you’re ready to bake, add the topping and pop it in the oven. You might need to add an extra 5-10 minutes to the baking time if it’s coming straight from the fridge.

Preparation Time	15-20 minutes
Cooking Time	35-45 minutes
Total Time	50-65 minutes
Level of Difficulty	Easy

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 800-900
• Protein: 15-20 g
• Fat: 60-70 g
• Carbohydrates: 40-50 g

Ingredients

• 2 cups sliced yellow squash (approximately 2 small ones)
• 2 cups sliced zucchini (around 2 small ones)
• 1/2 cup mayonnaise
• 2 tablespoons chicken stock
• 1 teaspoon lemon juice
• 1 teaspoon salt
• 1/2 teaspoon minced garlic
• 1/2 teaspoon coarse black pepper
• 1/4 cup grated parmesan cheese
• 1/4 cup panko breadcrumbs
• 2 teaspoons italian seasoning blend
• 2 tablespoons butter, melted

Step 1: Prepare the Oven and Baking Dish

Begin by preheating your oven to 350° Fahrenheit.

Generously butter a 2-quart baking dish or a small cast iron skillet to ensure the squash doesn’t stick during baking.

Step 2: Make the Sauce

In a large measuring cup, whisk together the mayonnaise, broth, lemon juice, salt, pepper, and garlic until smooth and combined.

Set this mixture aside for later use.

Step 3: Coat the Squash with Sauce

Slice both squashes into approximately 1/4 inch slices to ensure they bake to a crisp-tender texture.

Place the sliced squash in a large mixing bowl and pour the mayo/broth mixture over them.

Toss the squash slices until well coated with the sauce.

Step 4: Assemble the Casserole

Arrange the coated squash slices in the buttered baking dish, either neatly or simply spoon them in.

Pour any leftover sauce over the top of the squash to cover them with additional flavor.

Step 5: Prepare and Add Topping

In a small bowl, use a fork to mix together the panko, Parmesan, and Italian seasoning to create the topping.

Sprinkle this mixture evenly over the squash in the baking dish.

You can adjust the amount based on your preference.

Step 6: Bake and Broil

Cover the dish with foil and place it in the preheated oven.

Bake for 30 minutes to allow the squash to become perfectly tender.

Remove the foil, change the oven setting to broil, and brown the topping for 5-7 minutes until golden and crispy.

Be sure to keep an eye on it to prevent burning.

Step 7: Serve

Once the topping is beautifully browned, remove the dish from the oven.

Let it cool for a minute before serving warm as a delightful, savory side dish.

Enjoy!