Some side dishes steal the spotlight and end up being the star of the show – and this simple Spinach Casserole is just such a dish. It strikes that perfect balance between rich flavor and simple preparation, and it goes with all sorts of delicious mains like keto pork tenderloin or easy baked shrimp.
I love how the spinach melts down into the creamy, cheesy base without feeling overly heavy. Cottage cheese adds protein and a lovely texture, while Gruyère and Parmesan create that irresistible golden crust on top. It really does steal the spotlight of any keto meal!
I created this recipe recently because I wanted something a little different from my go-to sides like sautéed keto vegetables. I was craving something that tasted like comfort food and this recipe met the moment. I honestly didn’t expect it to be this good, but it was love at first bite.
Why You Will Love This Spinach Casserole
- So easy to make: Sauté the veggies, stir in the cheese, and bake until bubbly.
- Surprisingly delicious: I thought it would be good, but I didn’t know it would be this good!
- Everyday ingredients: Fresh spinach, cottage cheese, and a few simple seasonings come together to create something truly comforting.
- High protein: With almost 15 grams per serving, it helps make your meal extra satisfying.
- Goes with everything: Serve with chicken, pork, beef, or fish. It fits right into weeknight dinners or holiday celebrations.
- Make ahead option: Assemble it a day in advance and bake when ready, or refrigerate the leftovers for easy re-heating.
Ingredient Notes
- Butter: I sauté the veggies in butter for extra flavor, but you can also use olive oil.
- Onion: Only use a little onion because they add to the carb count. One quarter cup is just enough to add flavor.
- Garlic: I prefer the flavor from fresh garlic, but you can also use garlic powder.
- Spinach: I used fresh baby spinach, but you can also use frozen. Thaw it first and squeeze out the excess water before sautéing.
- Cottage cheese: Cottage cheese is a great addition to make the casserole even higher in protein. You can also use ricotta.
- Shredded cheese: I used gruyere for the filling as well as the top of the casserole, plus some Parmesan to play up the Italian flavor. But you could also use mozzarella or sharp cheddar.
- Kitchen staples: Egg, red pepper flakes, black pepper, and salt.
How to Make This Recipe
- Sauté the onion: Melt the butter and cook the onion until they start to soften. Stir in the garlic, salt, pepper, and red pepper flakes.
- Wilt the spinach. Add a few handfuls of spinach at a time, allowing it to cook down a bit before adding more. Cook until it is all wilted but not watery.
- Transfer to a bowl: Use a slotted spoon to leave any liquid behind in the pan. But be sure to get all the pieces of onion and garlic.
- Add the cheese: Mix in the cottage cheese, half of the gruyere, half of the parmesan, and the egg.
- Bake: Spread the mixture in a ceramic baking dish and top with the remaining shredded cheese and parmesan. Bake until the mixture is bubbly.
Tips for Success
Don’t overcook the spinach: Sauté until just wilted, as overcooking can make it watery. Draining off any excess moisture in the pan will also help keep the casserole from getting soupy.
Use high quality cheese: Gruyère adds wonderful flavor and meltability. Freshly grated Parmesan also gives the top a delicious golden crust.
Season to taste: If you are salt sensitive, consider skipping any additional salt. All three cheeses have plenty as it is.
Make it a meal: This spinach casserole could easily become the whole meal with some cooked chicken or sausage. Just stir it in along with the other ingredients in Step 5.
More Keto Casseroles to Love!
Spinach Casserole Recipe
Ingredients
- 1 tbsp butter, or olive oil
- 1/4 cup (40 g) chopped onion
- 4 cloves garlic, minced
- 15 ounces (425.24 g) fresh baby spinach, see notes for using frozen
- 1 tsp Italian seasoning
- 1/2 tsp salt
- 1/4 tsp pepper
- 1/4 tsp red pepper flakes
- 1 cup (210 g) cottage cheese
- 1 cup (132 g) gruyere cheese, shredded, divided
- 1/3 cup (33.33 g) grated Parmesan, divided
- 1 large egg
Instructions
- Preheat the oven to 375ºF.
- In a large skillet, melt the butter over medium heat. Add the onions and cook until beginning to soften, about 3 minutes. Add the garlic, Italian seasoning, salt, pepper, and red pepper flakes, and cook another minute.
- Add the spinach a few handfuls at a time, allowing it to cook down a bit before adding more. Cook until all of the spinach is wilted, about 5 minutes.
- Using a slotted spoon, transfer to a mixing bowl, leaving as much liquid in the pan as possible (be sure to get all the pieces of onion and garlic into the bowl).
- Add the cottage cheese, half of the gruyere, half of the parmesan, and the egg. Stir to combine well.
- Spread the mixture in a ceramic baking dish that holds 1.5 to 2 quarts. Top with the remaining shredded cheese and parmesan.
- Bake about 25 minutes, until the mixture is bubbly, and the cheese is melted and beginning to brown on top.
Notes
Nutrition
Frequently Asked Questions
Shredded mozzarella, Swiss, or even sharp cheddar will too. The flavor will change slightly, but the casserole will still be cheesy and delicious.
It’s great for up to 4 days in the fridge and can be easily rewarmed in the oven or the microwave.
This keto spinach casserole recipe has 5.6g of carbs and 1.7g of fiber per serving. That comes to 3.9g net carbs per serving.
Nutritional Disclaimer
Please note that I am not a medical or nutritional professional. I am simply recounting and sharing my own experiences on this blog. Nothing I express here should be taken as medical advice and you should consult with your doctor before starting any diet or exercise program. I provide nutritional information for my recipes simply as a courtesy to my readers. It is calculated using MacGourmet software and I remove erythritol from the final carb count and net carb count, as it does not affect my own blood glucose levels. I do my best to be as accurate as possible but you should independently calculate nutritional information on your own before relying on them. I expressly disclaim any and all liability of any kind with respect to any act or omission wholly or in part in reliance on anything contained in this website.
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This is so delicious!
This is a keeper. A great way to get spinach into our diet. Thanks
my family and I loved this recipe. I added leek, instead of onion and maybe a half cup of cream cheese and jong belegen instead of gruyere (I didn’t see it in the store). I didn’t have pepper flakes, so I used cayenne pepper. in sour of all of this, the dish was delicious. We made it the star on the plate, having used one leftover braadworst (husk off) and about 200 gr ground beef.
this was so flavorful and easy to make. I did a happy dance in my chair with almost every bite 🙂
Great to hear!
What percentage of cotton cheese do you use
Part skim.
This was so tasty!
A wonderful side dish that my entire family loved! Simply delicious and easy to substitute ingredients if you need to.
its an excellent side but I added diced Italian sausage to it and made it part of my main too. Really tasty.
Had almost a cup of cottage cheese so I made it up with a little ricotta. I’m onion intolerant so used a little onion powder and don’t buy Gruyère so I subbed in sharp cheddar and added 8 chicken tenders that I shredded up using my new protein shredder gizmo. After moving to SC I got rid of a lot of my casserole dishes, etc. I have a large rectangular slow cooker so I used the inner ceramic dish (think it is a lot bigger that 1.5-2 qt but any port in a storm) it was good enough to have a second helping!
Glad you enjoyed it!
This recipe looks great and is similar to something I make, but you left out the info on using frozen spinach. Could you please add that to the Notes and/or FAQ?
Please read the blog post more carefully, as the info is in there.
can’t I just use my cast iron fry pan for both stove top and oven and save myself all the dishes?
Sounds like you need to experiment.
Carolyn Ketchum says:
Please read the blog post as I already discussed shit. Thanks!
Oopsie?
I haven’t made this yet, but it looks delicious & the idea of adding chicken or sausage is brilliant for a full meal! I’m also a kale fan, so cooking that with the meat, & then adding it to the spinach dish sounds great. Even though it would raise the carb count, it would contain so many healthy nutrients!! Thank you Carolyn!!
I can’t wait to try this! But I don’t see any notes about using frozen spinach.
People keep saying that… but it’s there. Please make sure you are reading the blog post.
Look at the Ingredients Notes.
I’ve not made your recipe but I’ve been thinking about how to make it when I’m able. I’d make it and only eat the casserole because it reminds me of a frittata I made with VERY simlar ingredients. OMG.. I need to go make this now…. looks so heavenly. Thank you
Yes please, I would also like a bit more direction on how to use frozen spinach as I always have that in my freezer. Thanks so much!
Please read the blog post as I already discussed this. Thanks!
ooops Carolyn “shit” hahahahahahahahaha so funny, made my day
OMG! That’s supposed to say THIS, not shit. I am so sorry!
Discussed in the Ingredient Notes.
What are the notes for using frozen spinach?
There is a comment above under the ingredients description. Basically – thaw and drain liquid.
“Thaw it first and squeeze out the excess water before sautéing”
In the post she said: “I used fresh baby spinach, but you can also use frozen. Thaw it first and squeeze out the excess water before sautéing.”
Please read the blog post as I already discussed this. Thanks!