Summer Squash & Zucchini Gratin Casserole Recipe: Time to Pick That Zucchini From the Garden by Melissa Vickers

It’s coming up on that time of year when summer gardens are flourishing, and squash and zucchini are coming in faster than we know what to do about it. Try this creamy, cheesy squash and zucchini gratin casserole recipe that starts out on the stovetop and ends up in the oven. It tastes amazing and is really easy to prep and cook.

For this cheesy zucchini gratin recipe you'll need butter, zucchini, yellow squash, shallots, fresh garlic, heavy whipping cream, panko breadcrumbs and freshly grated Parmesan cheese. That's it!

Not only is this vegetable side dish delicious, there are so many health benefits of zucchini, too. Zucchini squash is loaded with vitamins, minerals and antioxidants, and is high in fiber and low in calories. Serve this vegetable dish with your favorite protein for dinner any day of the week.

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Cuisine: American
Prep Time: 10 minutes
Cook Time: 15 minutes
Total Time: 25 minutes
Servings: 4

Ingredients

• 2 tablespoons butter
• 2 medium zucchini, cut into 1/4-inch rounds
• 2 medium yellow squash, cut into 1/4-inch rounds
• 2 shallots, minced, or 1 medium onion, thinly sliced
• 1/2 teaspoon salt
• 1/4 teaspoon black pepper
• 4 garlic cloves, minced
• 1/2 cup heavy whipping cream
• 1 cup panko breadcrumbs (I used Italian-seasoned dry breadcrumbs), divided
• 1/2 cup grated Parmesan cheese (divided)

Helpful Products

• 2-Quart Casserole Dish
• Skillet

Recipe Notes

• Because we try to limit salt where we can, I opted to leave out the added salt and pepper and used Italian-seasoned panko crumbs.

• There's not need to peel zucchini or squash. The skin is loaded with nutrition! 

Here’s how to make it:

1. In a large skillet, melt butter over medium heat. Add zucchini, squash and shallots or onions. Sprinkle with salt and pepper. Cook, stirring occasionally, until vegetables are crisp-tender, about 4 to 5 minutes. Add garlic and cook for 1 minute.
   
2. Add the cream and cook until thickened, 3 to 5 minutes. Remove from heat and stir in 1/2 cup breadcrumbs and 1/4 cup cheese.
   
3. Spoon mixture into greased 2-quart casserole dish. Sprinkle with remaining breadcrumbs and cheese. Bake in a preheated 450-degree F oven until golden brown about 8 to 10 minutes.
   

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