Mock Lasagna Spaghetti Squash Casserole is serious low-carb comfort food, and you definitely won’t miss the carbs! We used spicy Italian sausage and three kinds of cheese in this tasty spaghetti squash lasagna.

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Mock Lasagna Spaghetti Squash Casserole with one serving on plate with fork and baking dish in back

Have you heard of spaghetti squash lasagna? I promise it’s absolutely a thing, and this Mock Lasagna Spaghetti Squash Casserole is a low-carb dinner idea with spaghetti squash replacing lasagna noodles. This recipe really knocked our socks off when we tested it!

In this mock lasagna casserole the traditional lasagna ingredients are layered with cooked spaghetti squash, and the spaghetti squash lasagna has the same flavors that make lasagna such a popular dish! If you like these lasagna flavors and you’re looking for dinner ideas, I promise this will be a winner!

The recipe is low in net carbs, and of course it’s much lower in carbs than traditional lasagna. And I love this lasagna casserole made with spaghetti squash and it’s perfect for fall, so I’m featuring this as my Friday Favorites pick this week.

What ingredients do you need?

What Marina Sauce did I use for the spaghetti squash lasagna?

I’m a huge fan of Rao’s Pasta Sauce (affiliate link) which is really low in carbs, and I’d use one of their sauces for this recipe if I didn’t have any of my Sausage and Basil Marinara Sauce in the freezer. Any low-sugar or purchased sauce will work for this recipe.

More methods for cooking the spaghetti squash:

If you want another method for cooking the spaghetti squash, you can cook the spaghetti squash in a crockpot or an Instant Pot for this recipe.

More Tasty Options for Low-Carb Lasagna:

Check out Ten Amazing Low-Carb Lasagna Recipes for even more tasty low-carb dinners with lasagna flavors!

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How to make Mock Lasagna Spaghetti Squash Casserole:

(Scroll down for complete printable recipe.)

  1. I roasted two spaghetti squashes for this, but if you have one large one (about 4 pounds), it will be plenty for the casserole. Microwave the squash about 5 minutes to soften, cut the spaghetti squash in half, scrape out seeds, rub with olive oil and Italian herb blend, and roast 50-60 minutes.  (Or cook the spaghetti squash in a crockpot or an Instant Pot if you prefer, but I think roasting does add flavor.)
  2. While the squash cooks, squeeze the turkey sausage out of the casings and brown well. 
  3. Add the marinara sauce, dried basil, Italian herb blend, and garlic powder and simmer until the liquid is mostly evaporated, about 30 minutes. 
  4. Mix together the cottage cheese, eggs, and Italian Herb blend.
  5. Make a layer of half the spaghetti squash in an 8 inch x 11 inch casserole dish. 
  6. Top with half the sauce, half the cottage cheese mixture, and half the cheese.
  7. Then make another layer of spaghetti squash, sauce, cottage cheese mixture, and the rest of the cheese. 
  8. Bake uncovered at 375F/190C for about 45 minutes.  (Mine got a little brown on the edges, but that didn’t bother us a bit.)
  9. Serve hot and devour!

Mock Lasagna Spaghetti Squash Casserole with baking dish and one plate of spaghetti squash lasagna

More Low-Carb Dinners with Spaghetti Squash:

Pesto Spaghetti Squash

Spaghetti Squash with Mizithra Cheese and Browned Butter

Greek Salad Spaghetti Squash Bowl

Twice Baked Spaghetti Squash With Kale

Spaghetti Squash and Chard Gratin

Weekend Food Prep:

This recipe has been added to a category called Weekend Food Prep where you’ll find recipes you can prep or cook on the weekend and eat during the week!

Mock Lasagna Spaghetti Squash Casserole finished dish with one serving on plate
Yield: 8 servings

Mock Lasagna Spaghetti Squash Casserole

Prep Time 1 hour 15 minutes
Cook Time 45 minutes
Total Time 2 hours

This Mock Lasagna Spaghetti Squash Casserole is serious comfort food, and you won’t miss the carbs in this tasty "lasagna" that features spaghetti squash.


Spaghetti Squash Ingredients:

  • 1 large spaghetti squash, about 4 pounds
  • 2 tsp. olive oil (for brushing squash)
  • 2 tsp. Italian Herb Blend (for sprinkling on squash before roasting)

Sauce Ingredients:

  • 2 tsp. olive oil
  • 19.5 oz. pkg. hot turkey Italian Sausage
  • 3 cups marinara sauce (see notes)
  • 1 tsp. dried basil
  • 1 tsp. Italian Herb Blend
  • 1 tsp. garlic powder (or use minced fresh garlic if you prefer)

Casserole Ingredients:

  • 2 cups cottage cheese
  • 2 eggs
  • 1 tsp. Italian Herb Blend
  • 2 cups grated Mozzarella
  • 1/2 cup coarsely grated Parmesan cheese


  1. Preheat oven to 400F/200C.
  2. If desired, microwave the spaghetti squash for about 5 minutes (to soften the skin so it’s easier to cut.)  Cut squash in half lengthwise and scrape out the seeds.  Brush the inside of each half with olive oil and sprinkle with Italian Herb Blend.
  3. Roast the squash on a flat baking sheet about 50-60 minutes, or until the squash strings apart easily with a fork.  (You can also cook the spaghetti squash in a crockpot or an Instant Pot for this recipe.)
  4. While the squash cooks,  heat the olive oil in a large non-stick frying pan, squeeze the turkey sausage out of the casings, and brown sausage well, breaking it apart with a turner while it cooks. (I like to use an old-fashioned Potato Masher (affiliate link) to break the sausage apart.)
  5. When the sausage is well-browned, add the 3 cups of sauce, dried basil, Italian Herb Blend, and garlic powder, and simmer on low until most of the liquid has evaporated, about 30 minutes.
  6. Put the cottage cheese into a bowl, add the eggs and Italian Herb Blend, and mix with a fork until the egg is well-mixed into the cottage cheese.
  7. Prepare grated Mozzarella and coarsely grated Parmesan.
  8. Spray an 8 inch by 11 inch casserole dish with non-stick spray.
  9. When the spaghetti squash is done, turn oven heat down to 375F/190C and let squash cool for a few minutes.  Then use a fork to scrape the squash away from the skin, separating it into strands of “spaghetti.”  Discard the skin.
  10. In the casserole dish, layer half the spaghetti squash, half the reduced sauce mixture, half the cottage cheese mixture, half the Mozzarella, and half the Parmesan.
  11. Repeat with another layer each of squash, sauce, cottage cheese mixture, Mozzarella, and Parmesan.
  12. Bake uncovered until the casserole is bubbling hot and the cheese is melted and lightly browned, about 40-45 minutes.
  13. Serve hot, with additional Parmesan cheese to add at the table if desired.


Use a 24 oz. jar or homemade marinara sauce. For purchased sauce I recommend Rao's Pasta Sauce (affiliate link) which has only 20 carbs in the whole bottle.

Recipe created by Kalyn.

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 421Total Fat: 23gSaturated Fat: 8gUnsaturated Fat: 11gCholesterol: 149mgSodium: 1419mgCarbohydrates: 13.2gFiber: 4gSugar: 10gProtein: 34g

Nutrition information is automatically calculated by the Recipe Plug-In I am using. I am not a nutritionist and cannot guarantee 100% accuracy, since many variables affect those calculations.

Did you make this recipe?

Did you make this recipe? Please leave a star rating (under the PRINT button in the recipe) or share a photo of your results on Instagram! THANKS!

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Low-Carb Diet / Low-Glycemic Diet / South Beach Diet Suggestions:
This recipe is great for low-carb diets and it’s also gluten-free. If you’re making this for the original South Beach Diet, they would recommend using low-fat cottage cheese and low-fat Mozzarella (as well as low-fat turkey Italian sausage.) For other types of low-carb diets, use full-fat cheese if you prefer, but I would prefer the less fatty turkey sausage for this recipe.

Find More Recipes Like This One:
Use Spaghetti Squash or Casseroles to find more recipes like this one. Use the Diet Type Index to find recipes suitable for a specific eating plan. You might also like to follow Kalyn’s Kitchen on Pinterest, on Facebook, on Instagram, on TikTok, or on YouTube to see all the good recipes I’m sharing there.

Historical Notes for this Recipe:
This spaghetti squash lasagna recipe was posted in 2015. It was last updated with more information in 2022.

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