Easy Cheesy Keto Meatball Casserole

The ultimate meatball casserole bubbles with juicy meatballs simmered in marinara, then blanketed in melted mozzarella and Parmesan under the broiler until golden. It leans on a batch of make-ahead freezer meatballs, so dinner comes together in about 45 minutes flat. Serve it with keto buns or zoodles and watch the whole pan disappear.

Your New Favorite Weeknight Hero: The Ultimate Meatball Casserole

Remember those classic, messy, absolutely delicious meatball subs? What if I told you that you could get all that comforting, saucy, cheesy goodness in a simple, low-carb casserole? This recipe is your weeknight hero. By using pre-made freezer meatballs, you get straight to the good part: bubbling marinara, tender meatballs, and a glorious blanket of melted mozzarella and Parmesan. Serve it with keto-friendly buns for the full sub experience, or spoon it over zoodles for a lighter meal. Let’s get cooking!

Ingredients

• 1 recipe marinara sauce, olive oil omitted
• 1/2 cup / 120 ml bone broth or chicken stock
• 1/2 recipe Make-Ahead Freezer Meatballs, approx. 32 meatballs
• 1 1/2 cups / 170 g / 6 oz shredded mozzarella cheese
• 1 cup / 90 g / 3.2 oz grated Parmesan cheese
• Salt and pepper, to taste
• Fresh basil, for garnish
• Sourdough Keto Buns or zoodles, for serving

Instructions

1. Prepare the marinara sauce according to its recipe, omitting the olive oil to prevent the final dish from becoming too greasy.2. Heat a large, oven-safe skillet or a casserole dish over medium heat. Add the marinara sauce, broth, and meatballs.3. Bring the mixture to a boil, then cover, reduce heat to low, and simmer. Cook for 10-12 minutes if using fresh meatballs, or up to 20 minutes for frozen meatballs.4. Remove the lid and continue to cook for another 5 minutes, allowing the sauce to thicken slightly.5. Preheat your broiler to high. Sprinkle the mozzarella and Parmesan cheese evenly over the meatballs.6. Place the skillet under the broiler and cook until the cheese is melted, bubbly, and lightly golden, about 5 minutes. Keep a close eye on it to prevent burning.7. Carefully remove from the oven. Season with salt and pepper to taste, garnish with fresh basil, and serve immediately.

Nutritional Information

• Recipe Facts & Nutrition
• MAKES: 8 servings (4 meatballs each)PREPARATION TIME: 15 minutesCOOKING TIME: 30 minutes
• NUTRITION FACTS PER SERVING:
• Energy: 443 kcal
• Net carbs: 3.6 g (0.13 oz)
• Protein: 31.8 g
• Fat: 32.5 g
• Macronutrient ratio: Calories from carbs (3%), protein (29%), fat (68%)

Pro Tips

• Use a cast-iron or other oven-safe skillet to go from stovetop to broiler, saving an extra dish.
• For a richer flavor, use beef bone broth instead of chicken stock.
• Ensure meatballs are in a single layer so they heat through evenly in the sauce.
• Let the casserole rest for 5 minutes after broiling; this allows the cheese and sauce to set, making it easier to serve.

FAQ

Q: Can I use frozen meatballs for this casserole
A: Yes, this recipe is designed to be made easily with pre-made freezer meatballs. Just be sure to simmer them in the sauce for up to 20 minutes to ensure they are heated through completely before adding the cheese.

Q: What should I serve with this low-carb meatball casserole
A: To keep the meal keto-friendly, serve the casserole with Sourdough Keto Buns for a classic meatball sub experience, or spoon it over zoodles for a lighter option.

Q: How do I make this recipe in one pan
A: For easy cleanup, use a large, oven-safe skillet (like a cast-iron pan). This allows you to cook the casserole on the stovetop and then transfer it directly under the broiler without needing a separate baking dish.

Q: How do I prevent my meatball casserole from being too greasy
A: The recipe recommends omitting the olive oil when you prepare the marinara sauce. This simple step helps prevent the final dish from becoming overly greasy from the combined fats.

Pro Tips

• Make the marinara without the olive oil for this dish — with the cheese and meatball fat going in, the extra oil would make the finished casserole too greasy.
• Keep the meatballs in a single layer so they heat through evenly in the sauce rather than steaming on top of each other.
• Use a cast-iron or other oven-safe skillet to go straight from stovetop to broiler — it saves an extra dish and holds heat beautifully under the broiler.
• For a richer flavor, use beef bone broth instead of chicken stock to loosen the sauce.
• Let the casserole rest for 5 minutes after broiling so the cheese and sauce set — this makes serving neat and tidy instead of soupy.

Frequently Asked Questions

Can I make this meatball casserole with frozen meatballs?

Yes — the recipe is designed for it. Simmer frozen meatballs in the sauce for up to 20 minutes (versus 10 to 12 for fresh) until heated through, then broil with the cheese.

Is meatball casserole keto-friendly?

Each of the 8 servings (4 meatballs each) has just 3.6 g net carbs with 31.8 g protein and 32.5 g fat. Skip the buns and serve over zoodles to keep it minimal.

How do I store and reheat leftovers?

Refrigerate the cooled casserole and rewarm gently in the oven so the cheese melts back over the sauce. A final minute under the broiler restores the golden top.

What should I serve it with?

Sourdough keto buns or zucchini noodles are the suggested pairings — the zoodles especially soak up the marinara without adding carbs.

Recipe card below.

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Stav Kogan

The Ultimate Meatball Casserole

Get all the comforting, saucy, cheesy goodness of a meatball sub in a simple, low-carb casserole. This weeknight hero uses pre-made freezer meatballs, bubbling marinara, and a glorious blanket of melted mozzarella and Parmesan.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 30 minutes mins

Total Time 45 minutes mins

Servings: 8 serving

Calories: 443

Ingredients Method Nutrition

Ingredients

  

1x2x3x?

• 1 recipe marinara sauce, olive oil omitted
• 1/2 cup (120 ml) bone broth or chicken stock
• 1/2 recipe Make-Ahead Freezer Meatballs, approx. 32 meatballs
• 1 1/2 cups (170 g) / 6 oz shredded mozzarella cheese
• 1 cup (90 g) / 3.2 oz grated Parmesan cheese
• Salt and pepper, to taste
• Fresh basil, for garnish
• Sourdough Keto Buns or zoodles, for serving
• Use a cast-iron or other oven-safe skillet to go from stovetop to broiler, saving an extra dish.
• For a richer flavor, use beef bone broth instead of chicken stock.
• Ensure meatballs are in a single layer so they heat through evenly in the sauce.

Method

 

1. Prepare the marinara sauce according to its recipe, omitting the olive oil to prevent the final dish from becoming too greasy. 2.
2. Heat a large, oven-safe skillet or a casserole dish over medium heat.
3. Add the marinara sauce, broth, and meatballs. 3.
4. Bring the mixture to a boil, then cover, reduce heat to low, and simmer.
5. Cook for 10-12 minutes if using fresh meatballs, or up to 20 minutes for frozen meatballs. 4.
6. Remove the lid and continue to cook for another 5 minutes, allowing the sauce to thicken slightly. 5.
7. Preheat your broiler to high.
8. Sprinkle the mozzarella and Parmesan cheese evenly over the meatballs. 6.
9. Place the skillet under the broiler and cook until the cheese is melted, bubbly, and lightly golden, about 5 minutes.
10. Keep a close eye on it to prevent burning. 7. Carefully remove from the oven.
11. Season with salt and pepper to taste, garnish with fresh basil, and serve immediately.
12. Let the casserole rest for 5 minutes after broiling; this allows the cheese and sauce to set, making it easier to serve.

Nutrition

Calories: 443kcalCarbohydrates: 3.6gProtein: 31.8gFat: 32.5g

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