Spaghetti Squash Casserole w/ Beef (Cheesy & Baked)
Developed and tested by Robyn Conley Downs
on Sep 23, 2024 (last updated Jul 11, 2025) 
If you’re craving a cozy, cheesy dinner that feels comforting but a little lighter than pasta, this spaghetti squash casserole with beef is just the thing! Tender strands of roasted squash get layered with savory ground beef and marinara sauce, then topped with a creamy ricotta blend and plenty of melty cheese; all baked until golden, bubbly, and perfect for an easy weeknight family meal.
5 star review
“Great recipe! More steps than I usually do but it was surprisingly easy and very delicious! Made with cottage cheese for added protein. Thank you for another great recipe. ”
– Evie
A Whole Lotta Love for This Spaghetti Squash Casserole
Spaghetti squash is such a fun, versatile veggie because once cooked it shreds into strands that look like angel hair pasta, which is one of the reasons I love using it in this cheesy baked casserole. It’s reminiscent of a tomatoey, cheesy Italian-style baked pasta dish, but, let’s be real, spaghetti squash is not exactly a pasta substitute – like we all know that it’s a vegetable and not pasta. Especially if you’re craving a baked casserole that’s packed with veggies, this one really is it!
To be clear, I’ve got nothing against carbs! If you want some real-deal pasta, you’ll love my viral zucchini beef casserole. And if you’re more of a meat and potatoes person, my super easy ground beef and potato casserole is just for you! Any way you go, you’ll get plenty of veggie love without getting weighed down. As always, I made the prep on this one super simple! Just be sure to give yourself enough time to prepare the spaghetti squash, which can be done up to 3 days in advance if you prefer.
They only thing to keep in mind is that when roasting the spaghetti squash you’ll just want to make sure it’s not overcooked or undercooked, because if you overcook the squash to the point where it’s super soft and fork tender, it will result in a mushy casserole; and if you undercook it, you won’t be able to separate the strands and risk ending up with a watery casserole.
For perfect “pasta-like” strands, you want to roast the squash to the point where it still has a bit of a crunch, so about 40 minutes. Roasting the squash first also allows some of the moisture to evaporate and help you avoid a watery casserole at the end. Once the squash is cooked and shredded, all you need to do is alternate layers of squash and marinara meat sauce, then top with dollops of the cheese mixture, sprinkle with a shower of cheese and bake. The finished casserole will come out bubbling with cheese and tomatoey goodness that’s begging for a side of this ultra simple garlic bread.
Welcome to My Kitchen! Let’s Make Spaghetti Squash Casserole
Spaghetti Squash Casserole w/ Beef (Cheesy & Baked!)
Ingredients
- 1 (2 ½ pound) spaghetti squash, see notes
- 2 teaspoons olive oil, plus more for roasting the squash
- ½ teaspoon kosher salt, plus more for roasting the squash
- 1 medium yellow onion, diced
- 1 pound lean ground beef
- 1 teaspoon no-salt added Italian seasoning
- 1 teaspoon granulated garlic powder
- 24 ounces marinara sauce
- 16 ounces ricotta cheese
- 1 large egg
- 1 cup mozzarella cheese, shredded
- ⅓ cup grated Parmesan cheese
- ¼ teaspoon freshly ground pepper
Equipment
Instructions
- Preheat oven to 375F.
Prepare the Spaghetti Squash
- Slice the spaghetti squash into 2-inch round slices. Using a spoon remove the seeds. Place the spaghetti squash rounds into a 9×13 ceramic baking dish. Drizzle with olive oil, sprinkle with salt, cover tightly with foil, and bake for 20 minutes. Uncover, flip the squash, cover and bake for an additional 20 minutes, or until the squash easily separates from the rind and into spaghetti-like strands, being careful not to overcook.
Prepare the Meat Sauce
- While the squash bakes, make the meat sauce by heating 1 teaspoon olive oil over medium high heat in a large pot or Dutch oven. Add the onion, sprinkle with ¼ teaspoon salt, and cook until just softened, about 3 minutes, stirring frequently.
- Add an additional 1 teaspoon of olive oil, then the beef. Sprinkle with ¼ teaspoon salt, the garlic powder, and the Italian seasoning, stirring to break the meat into small pieces. Cook until browned and cooked through, about 5-7 minutes, stirring occasionally.
- Turn off the heat. Drain any excess fat from the meat if desired, then add the marinara sauce and stir to combine.
Prepare the Cheese Sauce
- While the squash roasts, in a medium bowl, stir together the ricotta cheese, egg, ½ cup mozzarella, parmesan and black pepper until well combined.
Prepare the Casserole
- When the spaghetti squash is cool enough to handle, separate it from the rind into spaghetti-like strands. Discard the rind. Add the squash back to the same casserole dish (no need to wash the dish in between) along with half of the meat sauce, stirring until the sauce completely coats the spaghetti squash.
- Smooth the squash into an even layer, then top with the remaining meat sauce, again smoothing into an even layer.
- Dollop the cheese sauce on top, smoothing into an even layer. Sprinkle with the remaining ½ cup mozzarella.
- Cover with foil and bake for 20 minutes covered, then uncover and bake an additional 10 minutes until browned and bubbling.
- For more even slicing, allow to cool 10 minutes before serving.
Notes
- Spaghetti Squash: You’ll see instructions for how to roast your own spaghetti squash in this recipe. If you’d prefer to use store-bought or pre-cooked spaghetti squash, you’ll need about 6 cups of cooked squash.
- Don’t have ricotta cheese? I also tested this recipe with cottage cheese, which is an excellent substitute and boosts the protein in the recipe as well.
Because of salt restrictions, I made this recipe with no salt added cottage cheese, low sodium sauce and subbed mozzarella cheese, and it was still delicious!
I followed the instructions carefully when cooking the zucchini as sometimes it can add too much moisture to a casserole. This was cooked perfectly and my spouse and I both decided it is a “keeper” recipe!
Nancy, great tips on how to make this recipe lower in sodium, thanks for sharing! And thanks so much for leaving a reivew!
Great recipe! More steps than I usually do but it was surprisingly easy and very delicious! Made with cottage cheese for added protein. Came out a bit watery (should have cooked spaghetti squash longer) but was easy to dump off extra liquid. Thank you for another great recipe.
Evie, I’m so happy to hear this one was a hit and worth the extra steps! Thanks so much for taking the time to share your thoughts. 🙂