Zucchini Gratin

Zucchini Gratin is a delicious, creamy, cheesy casserole and a great way to use up some of that summer zucchini crop. This recipe is made grain-free making it gluten free and keto friendly. It’s an easy, tasty dish that the whole family will enjoy.

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We’ve been eating a lot of zucchini lately. Way more than usual, and not because I grew it in my garden (sadly, we didn’t have time to get a garden in this year). Shockingly, I have been growing tired with the same broccoli, Brussels sprouts, and even cauliflower sides. A good mix up was in order.

A few of our favorite ways to prepare zucchini is roasting it with summer squash, cherry tomatoes, and onions, then topping it with balsamic glaze, making Fried Zucchini Rounds, and in this recipe for Zucchini Gratin, also known as Zucchini Au Gratin.

They are all so good that I’m not sure which I like best, but this gratin has cream, Parmesan, and Gruyere in it, so you know it’s a winner!

Why This Recipe Works

This is an easy recipe that is simple and delicious. It’s made with crisp zucchini rounds, nutty Parmesan and Gruyere cheese, a creamy sauce and almond flour crumbs which adds a hint of sweetness. Almond flour crumbs are a grain free, low carb alternative to bread crumbs.

This is a very family friendly dish and a good one to help get your kids (or yourself!) to eat more vegetables. If you were lucky enough to have a garden this year, and have an abundance of zucchini, it’s a great way to use some up.

This recipe is grain free. Heavy whipping cream is brought to a boil to thicken, then mixed with cheese to make a thick, creamy sauce without the need for flour.

This makes the recipe gluten free, as well as low carb and keto friendly. There are 7 net carbs per generous serving.

How To Make Zucchini Gratin

What You Need To Make This Recipe

To make this recipe, you will need:

• 1 tablespoon unsalted butter
• 2 pounds zucchini, cut into 1/4-inch rounds (from about 4 medium zucchini)
• 1 shallot, finely diced
• 2 cloves garlic, minced
• 1 cup heavy whipping cream
• 1 teaspoon salt
• 1/2 teaspoon pepper
• 1/2 cup Parmesan cheese
• 1 cup Gruyere cheese, divided (I used a smoked Gruyere, but regular works just as good!)

To make the almond flour crumbs, you will need:

• 2 tablespoons unsalted butter
• 3/4 cup blanched almond flour

Chef’s Tip: if you’d prefer not to use almond flour crumbs, see the notes section of the recipe card at the bottom of the post for alternative toppings.

The entire recipe and instructions can also be found in the recipe card at the bottom of this post. You can also print the recipe from the card, if needed.

Prep!

Cut the zucchini into 1/4-inch thick rounds, finely chop the shallot, and mince the garlic. Grate the cheeses, if necessary.

Preheat your oven to 400°F.

Grease a large casserole dish using a small amount of butter or cooking spray.

Create!

Place a layer of zucchini rounds into the bottom of the casserole dish, overlapping them slightly. Set aside the remaining zucchini.

Chef’s Tip: This recipe will result in zucchini that is crisp-tender when done. If you’d prefer a very soft texture, you can precook the zucchini for a few minutes in a skillet in olive oil before layering it into the casserole dish.

Heat a large skillet over medium-high heat and add the butter. Once melted, add the shallot and garlic and cook for 2-3 minutes, stirring frequently, until softened.

Carefully pour in the heavy cream and raise the heat to high. Bring to a boil and cook another minute or so, until thickened slightly.

Remove the pan from the heat and stir in the Parmesan cheese and 1/2 cup of the Gruyere cheese.

 

Pour half of the cheese sauce over the zucchini in the casserole dish, then add a second layer of zucchini and the remaining sauce.

To make the almond flour crumbs, combine the almond flour and melted butter in a small bowl with a fork until crumbs form.

Using your fingers, break the crumbs up over the casserole and add the remaining Gruyere cheese.

Chef’s Tip: you will be able to break up bigger pieces of the almond flour crumbs more after cooking, if you’d like.

Bake, uncovered, for approximately 20 minutes, or until the almond flour crumbs and cheese are light brown and the zucchini is just fork-tender.

Present!

Serve hot.

Alternative Gratin Toppings

1. Use only the Gruyere cheese.
2. Make a pistachio topping (see this in the recipe for Brussels Sprouts Gratin – it’s SO good!).
3. Use crushed pork rinds.
4. If you’re not low carb, you can use regular or gluten free breadcrumbs.

Tips and Techniques

• If you prefer the zucchini to have a very soft texture rather than a crisp-tender one, you can precook it for a few minutes in a skillet in olive oil before layering it into the casserole dish.
• The larger almond flour crumbs can be broken up more after they are baked. They will have a crispy texture.
• Store leftovers in an airtight container in the refrigerator. Use within 3 days.

FAQ’s

What Is Gratin?

Gratin is a dish that is topped with bread crumbs and/or cheese and baked until lightly browned. This recipe uses a combination of almond flour crumbs and cheese as the topping to keep it low carb and keto friendly.

How Many Carbs Are In Zucchini?

There are approximately 6 grams of carbohydrates in one medium zucchini. 2 grams are fiber, leaving just 4 net carbs per zucchini.

More Keto Friendly Side Dishes

Here are a few more low carb side dishes that you may like:

• Keto Green Bean Casserole
• Keto Broccoli Casserole
• Keto Cauliflower Au Gratin

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