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Zucchini Gratin Casserole

Summer's bountiful harvest brings an abundance of fresh produce, including one vegetable that often multiplies faster than we can keep up with – zucchini. When your garden or local market overflows with these green gems, turn to our Zucchini Gratin Casserole for a versatile and delightful vegetable side dish. 

I look forward to the abundant supply of fresh produce that summer brings.  I also plant a small vegetable garden to ensure I will have plenty of my favorites like peas, beets, string beans, tomatoes, and zucchini.

Delicious Zucchini Gratin: A Summer Bounty Delight

A quick and easy summer squash casserole.

The trouble with zucchini is that there can be too much of a good thing.  What do you make when you have too much zucchini? That's when recipes like this Zucchini Gratin Casserole come in very handy.  You can use up a lot of zucchini with this recipe. 

Why You'll Fall in Love with This Recipe

Your Too Much Zucchini Solution: This gratin is the perfect way to put your surplus zucchini to good use. You can use up a substantial amount of zucchini with this delicious recipe, making it a go-to choice for gardeners and farmers' market enthusiasts.

Versatile and Easy: Zucchini Gratin is a versatile vegetable casserole that's incredibly easy to make. Plus, it's a dish that keeps on giving because the leftovers make a fantastic lunch the next day.

Creamy and Rich: The magic of this gratin lies in the luscious cream sauce. Heavy cream is cooked to perfection, thickening beautifully and infusing the dish with a rich and creamy texture that's simply irresistible.

Customizable Flavor: Zucchini's mild flavor serves as a canvas for your flavor creativity. Be generous with onion, garlic, salt, and pepper to elevate the taste to your liking. Feel free to adjust the recipe to suit your taste.

Tips for Success

1. Choose Medium-Sized Squash: For consistent results, opt for medium-sized zucchini. You can use all zucchini, all yellow squash, or a mix of both. Don't fret if you have oversized zucchini; just cut them into smaller pieces and remove large seeds if present.

2. Don't Skimp on Seasoning: Since zucchini is relatively mild in flavor, season generously with onion, garlic, salt, pepper, and Italian seasoning (if desired). These elements are crucial to infusing the dish with a burst of savory goodness. Start with my recipe and adapt it to your taste.

How to Make Zucchini Gratin

Serves Four-Six


You Will Need:
  • 2 Tablespoons olive oil
  • 4-6 medium zucchini, sliced into quarter-inch rounds
  • 1 medium onion, chopped
  • 4 cloves garlic, minced
  • 1/3 cup heavy cream
  • 1 teaspoon kosher salt
  • 1/2 teaspoon ground black pepper
  • 1 teaspoon Italian seasoning, optional
  • 1/2 cup panko bread crumbs
  • 1/2 cup grated Parmesan cheese
Preheat your over to 350 degrees F.  Heat the olive oil in a large skillet over medium-high heat.  Add the zucchini and the onion, spread in a layer across the pan.  Season with the salt, pepper, and Italian seasoning. Let the vegetables cook a few minutes until you start to see a little browning.  Then stir the mixture to get even color.  Cook until a little browned and crisp-tender.

Add the minced garlic to the pan and stir to combine.  Cook for about one minute.  Add the cream to the mixture, stirring to combine.  Let the cream bubble and thicken a bit. 

Combine the panko bread crumbs and the Parmesan cheese. Sprinkle half of the cheese mixture over the vegetables and stir to combine.  Spoon the mixture into a baking dish.  Top with the remaining cheese mixture.

Bake the mixture until the topping is browned and crisp, approximately 10-15 minutes.  Serve warm or at room temperature.

Frequently Asked Questions

Can I use other types of squash in this recipe?
Absolutely! You can experiment with different types of summer squash or even include other seasonal vegetables for variety.

Is there a dairy-free alternative to heavy cream?
Yes, you can use a dairy-free cream substitute like coconut cream or almond milk, which will add a unique flavor twist to the gratin.

Can I prepare this dish in advance?
Zucchini Gratin is best enjoyed fresh, but you can prep the components ahead of time. Cook the zucchini mixture, make the cream sauce, and store them separately. When ready to serve, combine the two, top with breadcrumbs and cheese, then bake until golden and bubbly.

The Zucchini Gratin Recipe

squash side dish, zucchini casserole
dinner
American
Yield: 6
Author: Donna Urso
Zucchini Gratin

Zucchini Gratin

An easy. delicious summer squash casserole, a perfect vegetable side dish.
Prep time: 10 MinCook time: 30 MinTotal time: 40 Min

Ingredients

Instructions

  1. Preheat your over to 350 degrees F. Heat the olive oil in a large oven-safe skillet over medium-high heat.
  2. Add the zucchini and the onion, spread in a layer across the pan. Season with the salt, pepper, and Italian seasoning. Let the vegetables cook a few minutes until you start to see a little browning. Then stir the mixture to get even color. Cook until a little browned and crisp-tender.
  3. Add the minced garlic to the pan and stir to combine. Cook for about one minute. Add the cream to the mixture, stirring to combine. Let the cream bubble and thicken a bit.
  4. Combine the panko bread crumbs and the Parmesan cheese. Sprinkle half of the cheese mixture over the vegetables and stir to combine. Spoon the mixture into a baking dish. Top with the remaining cheese mixture.
  5. Bake the mixture until the topping is browned and crisp, approximately 10-15 minutes. Serve warm or at room temperature.

Nutrition Facts

Calories

180.41

Fat (grams)

12.62 g

Sat. Fat (grams)

5.18 g

Carbs (grams)

12.8 g

Fiber (grams)

2.39 g

Net carbs

10.4 g

Sugar (grams)

5.6 g

Protein (grams)

5.88 g

Sodium (milligrams)

587.92 mg

Cholesterol (grams)

22.19 mg

Nutritional information is approximate.


Enjoy!




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