Cheesy, spaghetti squash lasagna casserole is beyond delicious. Even better? It's high protein, low carb, low calorie and gluten free! A healthier way to enjoy a timeless, Italian classic.

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This dish is easy to make and tastes so similar to regular lasagna, you won't feel like you're missing out on anything.
It's got everything you need including a creamy mixture of cottage, ricotta and mozzarella cheese, loads of Italian seasonings and a rich, meaty Bolognese (or ragu) sauce!
Want more healthy casserole recipes? Try these!
- Easy Low Carb Taco Casserole
- Sweet Potato Ground Beef Casserole
- Butternut Squash Casserole With Ground Beef & Rice
- One Skillet Zucchini & Squash Casserole
- Keto Zuppa Toscana
Ingredients for spaghetti squash lasagna casserole:
- Spaghetti squash: select a small squash at the grocery store, 3-4 pounds.
- Lean ground beef (93/7%): You could also substitute ground turkey, ground chicken or Italian sausage if preferred.
- Minced garlic: I always keep a jar of minced garlic in my refrigerator. I love garlic but don't always want to mince by hand, this is a great time saver!
- Tomato: canned petite diced tomatoes, tomato sauce and tomato paste.
- Italian seasonings, salt & pepper: flavor for days!
- Cheeses: low fat ricotta, low fat cottage & fresh shredded mozzarella cheese.
- Egg: mixed in with cheeses to add more flavor and fluff.
- Fresh parsley: for topping (if desired)!
How to make your casserole:
Keep scrolling for the full recipe and measurements. We’ll start here with a quick rundown!
Step 1: cook squash
Use preferred method to cook squash. I generally cut mine in half, remove seeds & pulp, and bake hollow side down. Add about a cup of water to your baking pan and cover the squash with aluminum foil, roast for 30-40 minutes at 400°F.
Step 2: make marinara meat sauce
Fully brown your ground beef (or turkey) and drain excess fat if necessary. Add minced garlic and sauté the two ingredients together for 30-60 seconds longer. Add diced tomato, tomato sauce, tomato paste, Italian seasonings, salt and pepper. Mix well and set aside (you can also use a high quality jar of marinara from the grocery store to save time)!
Step 3: make cheese mixture
Measure cottage, ricotta and half of your shredded mozzarella cheese into a small bowl. Add egg, Italian seasonings and pepper. Mix until well ingredients are well incorporated.
Step 4: assemble & bake
Preheat oven to 350°F and assemble your lasagna in six layers (I use an 8x8 baking dish). Spaghetti squash, cheese mixture, meat sauce, repeat.
Step 4: bake
Top your casserole with remaining mozzarella cheese. Place the 8x8 baking dish on top of a cookie sheet (in case of spillover) and bake for 30-40 minutes until bubbling.
HANDY TIPS:
- Thick or thin: I like a nice, thick lasagna so I assemble my casserole in an 8x8 baking dish (I always make sure to bake it on top of a cookie sheet in case of spillage). You can also make a thinner lasagna in a 9x13 dish if desired.
- Save some time: you don't have to create layers for this casserole to be delicious. You can also mix all of the elements together in a large bowl and then transfer to the casserole dish, cover with shredded mozzarella and bake.
- Store bought marinara: another great time saver? Buy a high quality jar of marinara sauce at the grocery store rather than making your own. Just don't go cheap or you might sacrifice on taste!
- Spaghetti squash: this recipe comes together much more quickly when you've already got cooked spaghetti squash on hand. I will often make mine ahead of time and freeze or refrigerate it for future use in casseroles like this.
Is spaghetti squash lasagna casserole keto?
This particular spaghetti squash casserole is definitely keto-friendly with approximately 10.5 net carbs per serving (of course, other recipes will vary depending on ingredients). However, most of the calories in this dish come from protein. So this meal will certainly help you avoid a high intake of carbs but it's not super high in fat content (something to note if you're tracking macros)!
More keto-friendly meals:
- Chicken Enchiladas With White Sauce
- One Skillet Chicken Thighs With Creamy Spinach Sauce
- Stuffed Peppers With Sausage & Cauliflower Rice
- Fettuccine Alfredo With Shrimp and Zucchini Noodles
- Spinach & Blue Cheese Stuffed Chicken Breasts
- Creamy Chicken Taco Soup With Rotel
- Ground Turkey Swedish Meatballs
Pin it for later!
Cheesy Italian Style Spaghetti Squash Lasagna Casserole
Ingredients
- 1 small spaghetti squash *3-4 lbs.
- 1 cup water
Meat/Bolognese Sauce
- 1 lb ground beef * I use 93/7% *see note below
- 1 & ½ teaspoons minced garlic *see note below
- 1 14.5 ounce can petite diced tomatoes
- 1 10 ounce can tomato sauce
- 2 tablespoons tomato paste
- 2 teaspoons Italian seasonings
- ½ teaspoon salt
- ½ teaspoon ground pepper
Cheese Topping & Mixture
- 1 cup low fat cottage cheese
- ½ cup low fat ricotta cheese
- 1 & ½ cups shredded mozzarella *divided (half for mixture, half for topping)
- 1 large egg
- 2 teaspoons Italian seasonings
- ½ teaspoon ground pepper
Optional Topping
- Fresh chopped parsley & parmesan cheese
Recipe notes:
Ground beef: you can also substitute ground turkey, chicken or Italian sausage! Minced garlic: I always keep a jar of minced garlic in my refrigerator. It's a huge time saver. I love garlic but don't always want to mince by hand, this is a great alternative!Instructions
- Preheat oven to 400°F. Cut spaghetti squash in half lengthwise, remove seeds and pulp.
- Measure 1 cup of water into a large baking dish. Place squash halves hollow side down in the pan, cover with aluminum foil and bake for 30-40 minutes, until tender. (*If you prefer to cook your squash in the crockpot or instant pot, this will also work fine).
- While squash is baking, make your meat sauce. Brown hamburger over medium low heat and drain excess fat.
- Add minced garlic to the meat, mix together and sauté for 30-60 seconds until aromatic. Now add your petite diced tomatoes (with juices), tomato sauce and tomato paste. Mix well and set your sauce aside.
- Now, to make your cheese mixture: combine cottage, ricotta and half of your mozzarella cheeses, egg, Italian seasonings and pepper in small bowl. Mix well and set aside.
- Turn the oven off and remove squash. Allow it to cool until you can handle it comfortably, then use a fork to remove squash strands from shell.
- When you are ready to start assembling your lasagna, turn the oven back on and preheat to 350°F.
- Place half of the cooked spaghetti squash in an 8x8 baking dish to create the first layer. For the next layer, use half of your cheese mixture. For the 3rd layer, use half of your meat sauce. Repeat for 6 total layers!
- Top with remaining shredded mozzarella cheese. and bake your assembled casserole for about 30-40 minutes, until bubbling.
- Allow to cool for 10 minutes, serve and enjoy!
Nutrition
Did you make this recipe?!
Wahoo! Thank you so much for trying it out – would you leave a rating and review in the comment section below?! Your feedback is so important to me.
Kim Waldorf says
Yummy! Looks simple and delicious. You already create a great recipe, Stacey! 💛
Garlic Salt & Lime says
Thank you so much, Kim!
Libbie Burling says
this looks delicious! Pinning for this weekend.
Cindy says
I'd be all over this but my husband no way. He wants my old-fashioned lasagna.
I love spaghetti squash. Have any recipes you can share?
Garlic Salt & Lime says
Oh I've got more coming! I'll let you know when they're available. Thanks, Cindy!
Jen says
I came across this while looking for new ways to use spaghetti squash! YUM!!
Garlic Salt & Lime says
I love how versatile spaghetti squash is!
Jacqueline Meldrum says
Oh my goodness I am absolutely drooling here.
Garlic Salt & Lime says
Thank you, Jacqueline!
Casey says
This was SO delish and easy! I used store bought marinara to make it even quicker! Worked just fine! Thank you!!!
Garlic Salt & Lime says
Oh yes, you can definitely use a store bought marinara to save time, great tip!!
RIKA says
This is a great way to utilize spaghetti squash. The perfect addition for a guilt-free casserole!
Garlic Salt & Lime says
I think so, too. Thanks, Rika!
[email protected] says
This sounds so good. Believe it or not, I have never tried spaghetti squash. After reading your recipe, now I really want to try it.
Garlic Salt & Lime says
Oh you should definitely give it a try (it's very tasty and versatile)! It's also very good as just a simple, spaghetti noodle substitute. Sometimes I'll bake my squash, scrape out the strands and then just top them with a yummy marinara and shredded cheese. Hope you enjoy!
Oscar says
Wow. This looks so good and love that it’s low carb. Making it this weekend.
Garlic Salt & Lime says
Hope you enjoy, Oscar!
Lindsay Howerton-Hastings says
This is so good! I usually don't use meat when I make spaghetti squash, but we really loved this version. Can't wait to make it again!
Garlic Salt & Lime says
I'm so glad to hear that, Lindsay!
Juliet says
Looks so hood, Stacey! I’m definitely saving this one. xo
Garlic Salt & Lime says
Woohoo! Hope you enjoy, friend!
Tammy says
OK, Stacey I need this recipe in my life. I gave up pasta and love Lasagna. You have saved me!
Garlic Salt & Lime says
This is a GREAT way to enjoy a classic without pasta!