Spinach gratin is a rich and creamy side dish with a layer of crispy but melty cheese on top. It's a delicious cross between Baked Spinach Dip and Creamed Spinach. Fresh spinach is blanched and tossed in a delicious creamy sauce, topped with mozzarella and Parmesan, and baked until golden perfection. This fancy side dish comes together quickly and easily with a handful of simple ingredients. It's also easy to make ahead and freezer-friendly!

Why You’ll Love Spinach Gratin
- The gratin technique. Gratin is a French technique where a shallow dish is covered with cheese or breadcrumbs before being thrown in a hot oven or broiler. The top layer becomes hot and toasty, forming a crispy layer that must be broken through.
- An easy way to work veggies into your meals. The most common French gratins are made from sliced potatoes such as Creamy Potatoes au Gratin or Ham and Potatoes au Gratin, but this recipe calls for a bunch of spinach. With the added heavy cream, cheese, and flour, even the most vegetable-averse people will love this cheesy side dish.
- It’s fast and easy—but it doesn’t look like it. When you pull this cheesy spinach gratin out of the oven, it looks like a masterpiece. But, it only takes around 30 minutes to make and most of that time is spent in the oven. And it requires simple ingredients that most people already have on hand.
Ingredients And Substitutions
To make this easy creamy spinach gratin, you will need the following ingredients (full quantities in the recipe card below):
- spinach - I used fresh spinach in this recipe, but you can also use a 24 ounce package of frozen chopped spinach. Allow it to thaw first and then squeeze it dry before adding it to the sauce.
- butter
- onion
- garlic
- all-purpose flour - you can also substitute with cornstarch to thicken the sauce.
- heavy cream
- Parmesan cheese - I used freshly grated Parmesan cheese because it adds the richest flavor. For convenience, you can also use pre-grated Parmesan.
- salt and pepper
- mozzarella cheese - you can substitute this with any melty cheese such as provolone, cheddar, and white cheddar.
You will also need measuring cups and spoons, a large skillet (I used my 12-inch cast-iron skillet), and a 9-inch square baking pan.
How To Make The Best Spinach Gratin
- Prepare spinach.Cut fresh spinach in half and cook in a large pot of boiling water for 30 seconds until wilted. Rinse the spinach under running cold water until cool to handle. Drain it in a colander and squeeze out excess water. Set aside.
- Sauté aromatics. In a large skillet, melt butter over medium-high heat until melted butter turns bubbly, about 1-2 minutes. Sauté onion and garlic until fragrant, about 2 minutes.
- Make the sauce. Add flour and stir well to combine. Stir in heavy cream and ¼ cup Parmesan. Stir constantly and turn the heat down to medium. Bring the mixture to a simmer until smooth and thickened, about 4-5 minutes. Season with salt and pepper to taste.
- Add spinach. Stir in spinach and toss well to coat. Cook for 1 -2 minutes until heated through.
- Bake. Transfer spinach mixture to a 9-inch square baking pan and top with mozzarella and remaining ¼ cup Parmesan. Bake in a 350F preheated oven for 20 minutes until cheese is melted and golden brown. Alternatively, you can place it under the broiler on high for 2-3 minutes until melted and golden. Keep a close eye on the broiler because things can burn quickly.
Recipe Tips and Tricks
- What to pair with spinach gratin: Spinach gratin is a versatile dish that tastes good with virtually any protein: chicken, beef, pork, fish, and anything else you can think of! It also tastes amazing with pasta, rice, and potatoes.
- Make ahead instructions: Make this recipe and assemble the spinach gratin up until the baking step. Then cover with plastic cling wrap and store in the refrigerator up to a day or 2, until ready to serve. If it has been sitting in the fridge for a while, you will need to add 10 minutes to the bake time.
- How to store: You can keep leftover spinach gratin in the fridge for up to 3-4 days. Cover the dish with plastic wrap or tin foil or transfer it to an airtight container before storing. You can also freeze it for up to 3 months.
- How to reheat: Reheat spinach gratin in a 350F preheated oven for 10-20 minutes until warmed through. You can also reheat it, covered, in the microwave in a microwave safe bowl on medium heat in 20 second intervals.
More Spinach Recipes
- Creamed Spinach
- Baked Spinach Dip
- Spinach and Feta Quiche with Cauliflower Crust
- Creamy White Chicken and Spinach Lasagna
- Spinach and Feta Turkey Burgers
- Turkey Tetrazzini with Spinach
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Recipe
Spinach Gratin
- Total Time: 35 minutes
- Yield: 6 servings
- Diet: Vegetarian
Description
Spinach gratin is a rich and creamy side dish with a layer of crispy melty cheese on top. This fancy side is easy to make ahead and freezer-friendly.
Ingredients
- 1 + ½ lb. fresh spinach (3 bunches), stems removed
- 2 tablespoons butter
- 1 small onion, diced
- 1 tablespoon garlic, minced
- ½ tablespoon all-purpose flour or cornstarch
- 1 + ½ cups heavy cream
- ½ cup Parmesan cheese, grated, divided
- 1 teaspoon salt (or to taste)
- ½ teaspoon ground black pepper
- 1 cup mozzarella cheese, shredded
Instructions
- Preheat oven to 350F.
- Cut fresh spinach in half and cook in a large pot of boiling water for 30 seconds until wilted. Rinse the spinach under running cold water until cool to handle. Drain it in a colander and squeeze out excess water. Set aside.
- In a large skillet, melt butter over medium-high heat until melted butter turns bubbly, about 1-2 minutes. Sauté onion and garlic until fragrant, about 2 minutes.
- Add flour and stir well to combine. Stir in heavy cream and ¼ cup of Parmesan. Stir constantly and turn the heat down to medium. Bring the mixture to a simmer until smooth and thickened, about 4-5 minutes. Season with salt and pepper to taste.
- Stir in spinach and toss well to coat. Cook for 1 -2 minutes until heated through.
- Transfer spinach mixture to a 9-inch square baking pan and top with mozzarella and remaining ¼ cup Parmesan. Bake for 20 minutes until cheese is melted and golden brown. Alternatively, you can place it under the broiler on high for 2-3 minutes until melted and golden. Keep a close eye on the broiler because things can burn quickly.
Notes
What to pair with spinach gratin: Spinach gratin is a versatile dish that tastes good with virtually any protein: chicken, beef, pork, fish, and anything else you can think of! It also tastes amazing with pasta, rice, and potatoes.
Make ahead instructions: Make this recipe and assemble the spinach gratin up until the baking step. Then cover with plastic cling wrap and store in the refrigerator up to a day or 2, until ready to serve. If it has been sitting in the fridge for a while, you will need to add 10 minutes to the bake time.
How to store: You can keep leftover spinach gratin in the fridge for up to 3-4 days. Cover the dish with plastic wrap or tin foil or transfer it to an airtight container before storing. You can also freeze it for up to 3 months.
How to reheat: Reheat spinach gratin in a 350F preheated oven for 10-20 minutes until warmed through. You can also reheat it, covered, in the microwave in a microwave safe bowl on medium heat in 20 second intervals.
- Prep Time: 5 minutes
- Cook Time: 30 minutes
- Category: Side Dish
- Method: Baked
- Cuisine: American
Suzanne says
Absolutely fabulous!! Best spinach gratin EVER!! Everyone loved it and it was comparatively easy, too.
Michelle says
I made this for Easter and my family and all of our guests LOVED IT!
I did end up bumping the amount of flour up a tad and reducing the heavy cream a little for a thicker sauce and it was fantastic.
I'm sure I'll be asked to make it again next year!
Kathi says
Great basic recipe - Made only 2 changes/additions - I added 4 oz cream cheese and 1/2 cup Mexican Blend cheese. I like my spinach really cheesy. Also, chopped the spinach before I wilted it in a large microwaveable bowl for 2 minutes. I have a big aversion to stringy spinach and perfer it chopped instead. Just my perference. Thanks for posting this recipe.
Leslie says
Kathi,
did you put the Mexican Blend cheese in the sauce or add to the top?