Craving cozy pasta flavors without the carb crash? This Keto Spaghetti Casserole gives you everything you love about a baked spaghetti dish—savory meat sauce, creamy cheese, and a bubbly top—minus the noodles. It’s simple, satisfying, and easy to make on a busy weeknight.
The texture is hearty, the sauce is rich, and the whole thing comes together in one baking dish. Whether you’re cooking for family or meal prepping for the week, this recipe is a reliable crowd-pleaser.
Ingredients
Method
- Prep the vegetable “noodles.” For spaghetti squash: halve, scoop seeds, brush with oil, and bake cut-side down at 400°F (200°C) for 30–40 minutes until strands pull easily with a fork. For zoodles: salt lightly and let drain in a colander for 15–20 minutes, then pat dry.
- Reduce moisture. If using spaghetti squash, spread the strands on a clean towel and gently squeeze to remove excess water. Too much moisture can make the casserole watery.
- Brown the meat. Heat olive oil in a large skillet over medium-high. Add onion and cook 3–4 minutes until translucent. Add garlic and cook 30 seconds. Add ground beef, season with salt and pepper, and cook until browned. Drain excess fat if needed.
- Build the sauce. Stir in marinara, Italian seasoning, and crushed red pepper if using. Simmer 5–7 minutes to thicken slightly. Taste and adjust salt and pepper.
- Make the creamy layer. In a bowl, combine cream cheese with ricotta or cottage cheese (if using). Microwave 10–15 seconds to soften if needed. Stir until smooth, then mix in 1/2 cup mozzarella and 1/4 cup Parmesan. Season with a pinch of salt and pepper.
- Assemble. Lightly grease a 9x13-inch casserole dish. Spread half the meat sauce on the bottom. Add all the veggie “noodles,” then dot and spread the creamy cheese mixture over them. Top with the remaining meat sauce.
- Add cheese. Sprinkle the top with the remaining mozzarella and Parmesan.
- Bake. Bake at 375°F (190°C) for 20–25 minutes, until bubbling around the edges and the cheese is melted and golden in spots. If you want more browning, broil for 1–2 minutes, watching closely.
- Rest and serve. Let the casserole rest 10 minutes to set. Garnish with fresh basil or parsley. Slice and serve warm.
Why This Recipe Works
This casserole swaps traditional pasta with low-carb veggie strands, so you still get that fork-twirling feel without the carbs. A mix of ground beef, marinara, and Italian seasoning keeps the flavor classic and bold.
Cream cheese and mozzarella add richness and hold everything together, making each slice tender but structured. The recipe uses everyday ingredients, doesn’t require a lot of steps, and is easy to customize based on what you have.
Shopping List
- Vegetable base: 2 medium spaghetti squash or 4–5 cups zucchini noodles (zoodles)
- Protein: 1 to 1.25 pounds ground beef (85–90% lean) or ground turkey
- Aromatics: 1 small yellow onion, diced; 3 cloves garlic, minced
- Marinara: 2 cups low-carb marinara sauce (look for no-sugar-added)
- Dairy: 4 ounces cream cheese, softened; 1/2 cup ricotta or cottage cheese (optional for extra creaminess); 2 cups shredded mozzarella; 1/2 cup grated Parmesan
- Fats: 1–2 tablespoons olive oil
- Seasoning: 1.5 teaspoons Italian seasoning; 1/2 teaspoon crushed red pepper (optional); salt and black pepper to taste
- Fresh herbs (optional): Basil or parsley for garnish
How to Make It
- Prep the vegetable “noodles.” For spaghetti squash: halve, scoop seeds, brush with oil, and bake cut-side down at 400°F (200°C) for 30–40 minutes until strands pull easily with a fork. For zoodles: salt lightly and let drain in a colander for 15–20 minutes, then pat dry.
- Reduce moisture. If using spaghetti squash, spread the strands on a clean towel and gently squeeze to remove excess water.
Too much moisture can make the casserole watery.
- Brown the meat. Heat olive oil in a large skillet over medium-high. Add onion and cook 3–4 minutes until translucent. Add garlic and cook 30 seconds.
Add ground beef, season with salt and pepper, and cook until browned. Drain excess fat if needed.
- Build the sauce. Stir in marinara, Italian seasoning, and crushed red pepper if using. Simmer 5–7 minutes to thicken slightly.
Taste and adjust salt and pepper.
- Make the creamy layer. In a bowl, combine cream cheese with ricotta or cottage cheese (if using). Microwave 10–15 seconds to soften if needed. Stir until smooth, then mix in 1/2 cup mozzarella and 1/4 cup Parmesan.
Season with a pinch of salt and pepper.
- Assemble. Lightly grease a 9×13-inch casserole dish. Spread half the meat sauce on the bottom. Add all the veggie “noodles,” then dot and spread the creamy cheese mixture over them.
Top with the remaining meat sauce.
- Add cheese. Sprinkle the top with the remaining mozzarella and Parmesan.
- Bake. Bake at 375°F (190°C) for 20–25 minutes, until bubbling around the edges and the cheese is melted and golden in spots. If you want more browning, broil for 1–2 minutes, watching closely.
- Rest and serve. Let the casserole rest 10 minutes to set. Garnish with fresh basil or parsley.
Slice and serve warm.
Storage Instructions
Let leftovers cool completely, then cover tightly or store in airtight containers. Refrigerate for up to 4 days. Reheat individual portions in the microwave until hot, or warm the whole dish in a 325°F (165°C) oven for 15–20 minutes.
For freezing, cut into portions, wrap well, and freeze for up to 2 months.
Thaw overnight in the fridge before reheating. If the casserole releases a bit of liquid after thawing, drain off excess and reheat uncovered to evaporate moisture.
Why This is Good for You
This casserole is low in carbs while offering high-quality protein and healthy fats, which support satiety and steady energy. Using spaghetti squash or zucchini adds fiber, potassium, and antioxidants without the starch load of pasta.
Cheese contributes calcium and flavor, so a smaller serving still feels satisfying. Overall, it’s a comforting meal that fits a keto or lower-carb approach without feeling restrictive.
What Not to Do
- Don’t skip moisture control. Neglecting to drain or dry your veggie noodles will make the casserole watery.
- Don’t use sugary marinara. Many jarred sauces add sugar. Choose a no-sugar-added option to keep carbs in check.
- Don’t under-season. Veggie noodles are mild.
Taste your sauce and cheese mixture, and adjust salt, pepper, and Italian seasoning.
- Don’t cut too soon. Resting 10 minutes helps the casserole set for cleaner slices.
- Don’t overcrowd with extra veggies. Mushrooms or spinach are great, but too many add moisture. Sauté and drain them well first.
Alternatives
- Different proteins: Try ground turkey, Italian sausage (look for no-sugar), or a mix for extra flavor. For a lighter option, use ground chicken and add a splash of olive oil.
- Veggie swaps: If you can’t find spaghetti squash, use zoodles or shirataki noodles.
Pat dry thoroughly to avoid excess moisture.
- Dairy-free: Use dairy-free cream cheese and shredded cheese alternatives. Add a beaten egg to the “noodle” layer to help bind.
- Spice it up: Add red pepper flakes, smoked paprika, or a pinch of fennel seed for Italian sausage vibes.
- White sauce version: Replace marinara with a keto Alfredo sauce and add sautéed spinach and chicken for a creamy twist.
FAQ
How many carbs are in a serving?
It varies by ingredients and portion size, but a typical serving lands around 6–9 net carbs when using spaghetti squash and a no-sugar-added marinara. Always check your labels and calculate based on your exact products.
Can I make it ahead?
Yes.
Assemble the casserole up to the cheese topping, cover, and refrigerate for up to 24 hours. Bake straight from the fridge, adding 5–10 extra minutes. For best texture, keep the “noodles” well-drained before assembling.
What’s the best low-carb marinara?
Look for sauces with no added sugar and 4–6 grams of net carbs per half cup.
Brands that list only tomatoes, olive oil, garlic, herbs, and salt are ideal. If the label includes sugar or corn syrup, skip it.
Can I add eggs to help it set?
Yes. Whisk 1–2 eggs into the cream cheese mixture if you want a firmer, more lasagna-like slice.
This is helpful if your veggies are on the wetter side.
Is spaghetti squash or zucchini better?
Both work well. Spaghetti squash has a slightly sweeter flavor and a more pasta-like strand. Zucchini is milder and faster to prep.
Choose based on taste and what’s available, and manage moisture either way.
Can I make it spicy?
Absolutely. Add extra crushed red pepper, a pinch of cayenne, or use hot Italian sausage. Balance the heat with a bit more cream cheese if needed.
How do I prevent a watery casserole?
Salt and drain zoodles, squeeze out excess liquid, and simmer your sauce until it thickens.
For spaghetti squash, roast until fully tender, then press out moisture with a towel. Avoid covering the casserole during baking.
What sides go well with this?
Keep it simple with a crisp green salad, roasted broccoli, or garlicky green beans. A drizzle of olive oil and lemon on the side salad keeps things bright and keto-friendly.
In Conclusion
This Keto Spaghetti Casserole is hearty, flexible, and easy to pull off on any weeknight.
You get big, comforting flavor and a satisfying texture without the carb-heavy pasta. With a few smart swaps and simple techniques, you can enjoy a classic baked “spaghetti” everyone will love—keto or not. Make it once, and it will quickly become part of your regular rotation.
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