All side dishes are not created equally. Creamy Spinach and Mushrooms Gratin is special and will elevate any meal. It’s simple enough to go with chicken or pork chops and elegant enough to stand up to a prime steak. Spinach blended with the earthy tones of mushrooms in a creamy cheese sauce, then baked to golden cheesy goodness. Sound fancy? It's actually a simple, no-angst recipe that definitely gives back a lot more than you put into it.
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[Publishers Note: I originally published the recipe Creamy Spinach with Mushrooms in May 2018. As with all the recipes I publish, I actually make them from time to time. I became a little disappointed with that recipe and it never did as well online as I had anticipated. I decided to reimagine this recipe and have now published this Creamy Spinach and Mushrooms Gratin here with more detailed step-by-step instructions and web-friendly images. I think this reimagined recipe is outstanding and will be one of your favorites. Give it a look. If you really like the original version, drop me an email and I will send you a copy of the original. Let me know what you think.]
Why is this recipe so good?
I've said this many times, side dishes are not an afterthought in South Louisiana. Spinach is such a versatile vegetable; it can be served raw in salads, simply sauteed in butter and garlic, or as part of elaborate recipes with a wide variety of other ingredients. It's not uncommon to see spinach in stuffings, dressings, and soups.
This particular recipe is an example of what a Creole cook may create from a variety of fresh ingredients available at the market. It blends a creamy cheese sauce made with smoked gouda and romano cheese into spinach and mushrooms, then bakes it all together under a sprinkling of more cheese!
Smoked Gouda provides a rich, mild flavor that is a good contrast to the sharp bite of the Romano. Fresh mushrooms add an earthy dimension to the dish's richness. There are other cheese options that may be good substitutes in the Hints and Tips section below. Creamy Spinach with Mushroom Gratin elevates every meal to exceptional and memorable.
Here’s What You Need
Here are some of the key ingredients for this recipe:
Check out the Hints and Tips below for a little more on spinach, mushrooms, and cheese.
Here is some of the equipment I used to prepare this recipe:
Here’s What You Do
First…you have a beer. How can you make this recipe even simpler than it naturally is? Preparation. Your mise en place includes completely reading the recipe, making sure you have all the ingredients and equipment and preparing yourself and the ingredients so that all you have to do is concentrate on the process. It all starts with a beer!
Mise en place
This is the key to a no-angst cooking experience. Start by cooking the spinach according to the directions on the package. Once the spinach is cooked, place it in a strainer to drain. Prior to using the spinach, squeeze out the remaining liquid by hand or in a tightly twisted clean kitchen towel. Lightly clean the mushrooms and cut them into quarters (See the Hints and Tips section for more on the mushrooms). Finely chop the shallots and the garlic, grate the cheese and measure the remaining ingredients. All the prepared ingredients should be placed in their own prep bowls, laid out so all you have to do is focus on the process. Preheat the oven to 350 degrees Fahrenheit. How’s your beer?
Build the first level of flavor with the vegetables
What happens in this step? The flavor is built in layers and this is the first layer, the foundation. We start by rendering the liquid from the mushrooms, which intensifies the flavor that is carried throughout the cooking process.
In a heavy-bottomed Dutch oven, melt the butter over medium-high heat. Add the mushrooms and saute for 8 to 10 minutes, while they start to brown and release their liquid.
Once the liquid has reduced, add the shallots and saute for about 3 to 4 minutes until starting to get clear.
Once the shallots are soft and clear, add the garlic and the Herb and Spice Blend. It only takes a couple of minutes before they are aromatic, which is what you want.
Deglaze the Dutch oven with the dry white wine over medium-high heat.
Once completely reduced, add the drained spinach and mix well to combine all of the ingredients.
A Note on the Wine: Don't skip this step. I use a dry white wine, like vermouth. The recipe calls for only ½ cup and it is used to deglaze the bottom of the Dutch oven after the mushrooms, shallots, garlic, and Herbs and Spices have been sauteed. The wine will almost completely evaporate, intensifying its flavor, but it's the deglazing of the fond that adds the most significant flavor. Substitute water or apple juice if you don't have wine.
Make the cheese sauce
What happens in this step? The cheese sauce is the catalyst to this great recipe. It starts with a basic bechamel sauce then adds two types of grated cheese for creaminess and depth of flavor.
Warm the milk in the microwave for a couple of minutes. Adding cold milk to the roux will likely result in lumps!
In a suitably sized saucepan, melt the butter until bubbly, then add the AP flour. Using a whisk or wooden spoon, blend the butter and flour into a thick, blond roux for about 2 to 3 minutes. Do not let the roux brown, but a couple of minutes will cook out the flour taste. Remove the saucepan from the heat. Add the warmed milk a little at a time, blending thoroughly with the roux before adding more warmed milk. Add about ¼ cup at a time until half of the milk has been added, then you can increase the amount of milk you add. Once all blended together, return the saucepan to medium heat and simmer, stirring or whisking regularly. After about 5 minutes, add about 1 ½ cups of grated smoked gouda and about ¼ cup of Romano cheese. Blend together completely.
Mix the cheese sauce with the spinach
What happens in this step? We bring the spinach and mushrooms together with the cheese sauce. This will be baked to a perfect consistency.
You will have about 2 cups of cheese sauce. Start by adding about half the cheese sauce into the spinach and mushrooms. Mix thoroughly to combine. Add more cheese sauce, a little at a time, until you have the consistency that you are looking for. At this point, taste the spinach mix for seasoning. Add more kosher salt and pepper if needed and even add more cheese and Creole seasoning if you feel it needs them. Remember that we will sprinkle some cheese on top to finish, so keep that in mind if wanting to add more cheese.
Bake the cheesy spinach
What happens in this step? Using a baking dish, we will top the creamy spinach mix with more grated cheese and bake to a golden brown. The baking step blends the various flavors into one delicious dish.
Prepare a shallow baking dish by spreading softened butter all over the inside.
Roll the creamy spinach mix into the baking dish and spread to an even thickness. Next top the spinach with about ½ to 1 cup of grated gouda cheese, then top that with a couple of tablespoons of grated Romano cheese. Place the baking dish into the preheated oven, uncovered, for about 30 minutes or until the top has browned and it’s bubbly around the sides. When ready, remove the baking dish from the oven and let it sit for about 5 to 10 minutes.
Hints and Tips (FAQs)
Keep leftover spinach casserole in an airtight container refrigerated for 3 to 5 days. It can also be frozen for about 6 months. Make sure to freeze the spinach dish in an airtight container and thaw in the fridge overnight. Reheat covered in a 350-degree oven for about 10 to 15 minutes or until warmed all the way through. This can also be reheated in the microwave.
Well, we know it makes you strong. Just ask Popeye! Spinach is high in Vitamins like E and is full of minerals, magnesium, and iron among many other minerals. This veggie is low in calories and is a boost to our immune systems. Check out this article, to learn more about the health benefits of spinach. Of course in this recipe, we add some dairy products, so check out the nutrition label on the recipe card to see the overall nutrition of Spinach Casserole.
This recipe is perfect for frozen spinach. You should use your favorite brand, but mine is the one that comes in a pouch and can be steamed in the microwave. Fresh spinach is also fine. You’ll need at least 2 pounds of fresh spinach. You should saute the fresh spinach in a little butter until fully wilted. Make sure to drain and squeeze out any water that is retained in the spinach, whether it's fresh or frozen.
I use Baby Bellas which have a rich, earthy flavor. I cut them in quarters so there are chunks of mushrooms throughout the dish, but sliced will also be fine. You can substitute white button mushrooms, portobellos, or even shiitake mushrooms. Mushrooms have varying amounts of water, so the saute time will vary depending upon the type of mushroom you choose.
I use smoked gouda and grated romano cheese for this recipe. Smoked Gouda is a smooth, rich cheese that melts well and adds some complexity to the flavor profile. The Romano’s sharp, tart taste is a great balance to the creamy smoothness of the gouda. Good substitutes are Gruyere Cheese, Cheddar (smoked cheddar is good!), Monterey Jack and Pepperjack. Even a combination of some of these cheeses is great in this recipe. Make sure to use a cheese that melts and blends well.
Here are some Main Dishes that would be a perfect match for this dish:
More Cajun and Creole dishes:
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Yeah You Right!
Creamy Spinach and Mushroom Gratin
Here's What You Need
- 20 ounces Frozen Spinach cooked according to directions on package
- 2 tablespoons Butter
- 6 ounces Crimini Baby Bella Mushrooms Quartered
- 2 tablespoons garlic about 3 cloves - Chopped fine
- 3 tablespoons small Shallot sliced
- ½ cups Dry White Wine
- ½ cup Romano Cheese Grated - divided
- 2 cups Smoked Gouda Cheese in all grated
For the Bechamel
- 4 tablespoons butter
- 3 tablespoons AP Flour
- 2 cups whole milk heated
Herb and Spice Blend
- 1 teaspoons creole seasoning
- ½ teaspoons kosher salt
- ½ teaspoon ground black pepper
Here's What You Do
- Cook spinach as directed on the package; drain and squeeze out water
- Cut the mushrooms into quarters, finely chop the shallots and garlic
- Grate the cheese, measure remaining ingredients
- Prepare a baking dish with butter, preheat the oven to 350 degrees Fahrenheit
Combine the spinach and vegetables
- Add 2 tablespoons of butter to Dutch oven over medium heat
- Add the mushrooms and sauté them for about 10 minutes, until liquid is released and reduced
- Add the shallots and sauté until starting to clear-about 3 to 4 minutes.
- Add the garlic and the Herb and Spice Blend. Mix well and sauté until aromatic-about 1 to 2 minutes
- Continue sautéing mushrooms and spices for another 2 or 3 minutes, until starting to brown, stirring often so it doesn't stick.
- Deglaze the Dutch oven with white wine. Using your spoon, loosen the fond off the bottom of the pan and stir that into the mushrooms. Allow the wine to reduce down almost completely.
- Add the spinach to the mushroom mixture and stir to thoroughly blend all ingredients. Set aside.
Prepare the Cheese Sauce
- Warm the milk in the microwave or in a saucepan.
- Melt the butter in a large saucepan over medium heat.
- Add the AP flour and whisk to make a blond roux; about 3 minutes.
- Remove the saucepan from the heat and add the warmed milk about ¼ cup at a time, whisking to combine completely with the blond roux before adding more milk.
- Once about half of the milk has been added, it's OK to add the remaining milk.
- Once the milk has been thoroughly blended with the roux, return the saucepan to the heat and bring to a simmer. Maintain a simmer for about 4 or 5 minutes, whisking constantly. When the sauce coats the back of a spoon it is ready.
- Add 1 to 1 ½ cup of grated gouda cheese and 2 tablespoons of Romano cheese to the bechamel sauce and combine thoroughly.
Combine and Bake
- Add about 1 ½ cups of the cheese sauce to the spinach and blend well. (You may add more or less than 1 ½ cups of cheese sauce if you desire)
- Taste for seasoning and add salt and pepper as needed.
- Fold the spinach/cheese mixture into the prepared baking dish.
- Top the spinach mixture with the remaining grated gouda cheese and sprinkle romano cheese on top
- Place the baking dish, uncovered, into a preheated 350-degree oven for about 30 minutes or until browned on top and bubbly around the sides.