Name: Easy Zucchini Casserole Recipe
Prep time: 15 min
Cook time: 40 min
Total time: 55 min
Ingredients: 4 cups zucchini (diced into 1-inch pieces); 1 cup mayonnaise; 1 cup shredded cheddar cheese; 2 eggs (slightly beaten); 1 tsp pepper; 3/4 – 1 tsp garlic powder; 1/4 cup panko breadcrumbs; 1 Tbsp butter (melted)

This easy zucchini casserole recipe is the dish you never knew your weeknight dinner rotation was missing. Creamy, cheesy, and topped with a golden, buttery breadcrumb crust — it checks every box. Whether your garden is bursting with zucchini or you just grabbed a few from the store, this recipe turns a humble vegetable into pure comfort food. With just 8 simple ingredients and minimal prep time, you’ll have a bubbling, crowd-pleasing casserole on the table in under an hour.

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Why You’ll Love This Recipe

Super simple to make. This recipe requires no fancy techniques — just chop, mix, and bake. It’s a perfect beginner-friendly dish that delivers impressive results every time.
Incredibly creamy and cheesy. The combination of mayonnaise, shredded cheddar, and eggs creates a rich, custardy filling that tastes indulgent without being overly heavy.
A great way to use up zucchini. If your garden is going wild this summer, this casserole is one of the tastiest ways to put all that zucchini to good use.
That irresistible crispy topping. The panko breadcrumbs tossed in melted butter bake up beautifully golden and crunchy — a perfect contrast to the creamy filling underneath.
Crowd-pleasing comfort food. This dish works as a hearty side or a light main course, and both kids and adults tend to go back for seconds.

Ingredients

4 cups zucchini, diced into 1-inch pieces
1 cup mayonnaise
1 cup shredded cheddar cheese
2 eggs, slightly beaten
1 tsp pepper
3/4 – 1 tsp garlic powder
1/4 cup panko breadcrumbs
1 Tbsp butter, melted

Notes & Substitutions: If you prefer a lighter version, you can swap the mayonnaise for plain Greek yogurt or a mix of half mayo and half sour cream — the texture stays creamy and delicious. Sharp cheddar adds a bolder flavor, but mild or medium cheddar work just as well. Regular breadcrumbs can replace panko in a pinch, though panko delivers a crunchier, more satisfying topping. Feel free to adjust the garlic powder to your taste — the full teaspoon gives a lovely savory punch.

Instructions

Preheat your oven to 350°F (175°C). Lightly grease a 9×9-inch or similar-sized baking dish with cooking spray or a little butter. This prevents sticking and makes cleanup easier.
Dice the zucchini into 1-inch pieces, keeping the pieces uniform so they cook evenly. Pat them dry with a paper towel if they feel very wet — this step helps prevent a watery casserole.
Mix the filling. In a large mixing bowl, combine the mayonnaise, shredded cheddar cheese, slightly beaten eggs, pepper, and garlic powder. Stir everything together until well blended. The mixture should look thick and creamy — that’s exactly what you want.
Fold in the zucchini. Add the diced zucchini to the bowl and gently stir until every piece is well coated with the creamy mixture. Transfer everything into your prepared baking dish and spread it out into an even layer.
Make the breadcrumb topping. In a small bowl, stir together the panko breadcrumbs and melted butter until the crumbs are evenly coated. Sprinkle the mixture evenly over the top of the casserole. This buttery layer will toast up into a gorgeous golden crust as it bakes.
Bake for 35–40 minutes, or until the top is golden brown and the center is set and no longer jiggly. You can insert a toothpick or small knife into the center — it should come out clean. If the top is browning too quickly, loosely tent it with foil for the last 10 minutes.
Rest before serving. Let the casserole sit for 5 minutes after pulling it from the oven. This helps it firm up slightly so it slices and serves cleanly.

Pro Tips & Troubleshooting

Most common mistake: Skipping the step of patting the zucchini dry. Zucchini holds a lot of moisture, and if you don’t remove some of it upfront, your casserole can turn out watery and soupy.

Technique tip: Slightly beating the eggs before adding them helps them incorporate more evenly into the mayo and cheese mixture, creating a smoother, more cohesive filling.

Technique tip: Don’t skip the butter on the panko — dry breadcrumbs won’t brown nearly as well and can end up pale and chalky on top.

Troubleshooting: If your casserole looks liquidy after baking, it likely needed a few more minutes in the oven. Pop it back in for 5–10 more minutes until the center is fully set.

Serving, Storage & Variations

Serving: This casserole pairs beautifully alongside grilled chicken, pork chops, or a simple green salad. It also works wonderfully as a light vegetarian main served with crusty bread.

Storage: Store leftovers covered in the refrigerator for up to 4 days. Reheat individual portions in the microwave for 1–2 minutes, or warm the whole dish in a 325°F oven for about 15 minutes to revive the crispy topping.

Variations:

Add protein: Stir in 1 cup of diced cooked chicken or crumbled bacon for a heartier casserole.
Spice it up: Add a pinch of red pepper flakes or a dash of hot sauce to the filling for a little heat.
Mix up the cheese: Try a blend of mozzarella and parmesan for a slightly different, equally delicious flavor profile.

Nutrition Information

Nutrition values are estimated per serving based on 6 servings. Actual values may vary depending on specific brands and ingredient substitutions used.

Nutrient	Per Serving
Calories	320 kcal
Protein	7 g
Carbohydrates	7 g
Fat	29 g
Fiber	1 g
Sugar	3 g
Sodium	380 mg

Frequently Asked Questions

Can I make this easy zucchini casserole recipe ahead of time?

Yes! You can assemble the casserole up to 24 hours in advance and store it covered in the refrigerator. Add the breadcrumb topping just before baking so it stays crispy.

Do I need to peel the zucchini before dicing it?

Nope — the skin is tender and completely edible, so there’s no need to peel it. Leaving the skin on also adds a little extra color and nutrition to the dish.

Can I freeze this casserole?

Freezing is possible but not ideal, as the mayo-based filling can separate slightly upon thawing. For best results, enjoy it fresh or refrigerated within 4 days.

Conclusion

This easy zucchini casserole recipe truly proves that simple ingredients can create something seriously special. Creamy on the inside, golden and crispy on top, and full of cheesy, garlicky flavor — it’s the kind of dish that disappears fast at the dinner table. Whether you’re a zucchini lover or just looking for a new family favorite, this one is sure to earn a permanent spot in your recipe collection. Give it a try, and let me know how it turns out in the comments below! Don’t forget to rate the recipe and tag your photos — I’d love to see your creation!