There’s something so comforting about a warm casserole coming straight out of the oven, bubbling with cheese and full of rich flavor.
This Spaghetti Squash Casserole with Ground Beef has all the heartiness of a baked pasta dish—but without the heavy carbs.
Why I Love This Recipe
Lower-carb than traditional pasta bakes
Packed with protein and veggies
Naturally gluten-free
Reheats beautifully—hello, leftovers!
A great way to use up squash in fall or winter
What You’ll Need (Ingredient Highlights)
Spaghetti squash – When baked, its strands mimic spaghetti but are lighter and more nutritious.
Lean ground beef – Hearty and flavorful, keeps the dish satisfying.
Onion & garlic – The aromatic base for building flavor.
Diced tomatoes & tomato paste – Create depth and body for the sauce.
Marinara sauce – Adds sweetness and moisture.
Italian seasoning – For that classic herby touch.
Mozzarella cheese – Melts beautifully into a golden, bubbly topping.
Pro Tips Before You Start
Roast the squash cut-side down for caramelized flavor.
Use a fork to fluff the squash strands—don’t mash!
Drain beef well after browning to avoid excess grease.
Add red chili flakes if you like a spicy kick.
Make it ahead and bake right before dinner.
How to Make Spaghetti Squash Casserole with Ground Beef
Step 1: Roast the Squash
Preheat oven to 400°F (204°C).
Cut the spaghetti squash in half lengthwise and scoop out seeds.
Drizzle with olive oil, season with salt and pepper, and place cut-side down on a parchment-lined baking sheet.
Roast for 35–40 minutes until fork-tender.
Step 2: Scrape the Squash
Let the squash cool for 10–15 minutes.
Use a fork to gently scrape the flesh into long, spaghetti-like strands. Set aside.
Step 3: Cook the Beef Mixture
Preheat oven to 375°F (190°C).
In a skillet over medium heat, brown the ground beef with diced onion and garlic until no pink remains. Drain excess fat.
Step 4: Build the Sauce
Add diced tomatoes, tomato paste, marinara sauce, and Italian seasoning.
Stir and simmer for 5 minutes to blend flavors.
Step 5: Combine with Squash
Add the roasted squash strands to the skillet and mix well until fully combined with the sauce.
Step 6: Assemble & Bake
Transfer mixture to a baking dish (or scoop back into squash shells for fun presentation).
Top with shredded mozzarella cheese.
Bake for 20 minutes, or until cheese is melted and golden.
What to Serve It With
A side salad with vinaigrette
Garlic knots or crusty bread
Roasted green beans or broccoli
A glass of light red wine
Variations / Substitutions
Swap beef for ground turkey or chicken.
Use dairy-free cheese for a lactose-free version.
Add spinach, mushrooms, or chopped bell peppers.
Stir in a spoonful of ricotta or cottage cheese for extra creaminess.
Storage & Leftovers
Fridge: Store in an airtight container for up to 4 days.
Freeze: Wrap tightly and freeze for up to 2 months.
Reheat: Use microwave or 350°F oven until warmed through.
Repurpose: Spoon leftovers into bell pepper halves and bake for stuffed peppers!
FAQs
Is spaghetti squash healthy?
Yes! It’s low in calories and carbs and high in fiber and vitamins.
Can I prep the squash ahead of time?
Absolutely—roast it 1–2 days in advance and refrigerate until ready to use.
What’s the best way to cut spaghetti squash?
Use a large, sharp knife and slice carefully lengthwise.
Microwave it for 3–4 minutes to soften if needed.
Can I use jarred pasta sauce?
Yes, use your favorite marinara or tomato basil sauce.
Can I make this vegetarian?
Yes, skip the meat and add more veggies like mushrooms or lentils.
Does this dish freeze well?
It freezes great—just thaw overnight in the fridge before reheating.
Can I add cheese inside the mixture?
Totally! Stir in some ricotta or even a handful of mozzarella before baking.
Final Thoughts
This Spaghetti Squash Casserole with Ground Beef proves you don’t need pasta to enjoy a hearty, cheesy comfort dish.
It’s simple, full of flavor, and easy to adapt to whatever you have on hand.
Whether you’re trying to eat low-carb or just want to sneak in more veggies, this one’s a winner every time.
Spaghetti Squash Casserole
Ingredients
- 1 medium spaghetti squash cooked
- 1 lb lean ground beef
- 1 small onion diced
- 2 cloves garlic minced
- 1 can 15 oz diced tomatoes
- 1 tbsp tomato paste
- 1 cup marinara or pasta sauce
- 1 tsp Italian seasoning
- 1 ½ cups shredded mozzarella cheese
Instructions
- Roast spaghetti squash at 400°F until tender, about 35–40 minutes.
- Let cool and scrape into strands.
- Preheat oven to 375°F.
- In a skillet, cook ground beef, onion, and garlic until no pink remains. Drain excess fat.
- Stir in diced tomatoes, tomato paste, marinara sauce, and Italian seasoning.
- Simmer 5 minutes.
- See full steps with tips & photos → https://mischacrossing.com/spaghetti-squash-casserole/
