Low Carb Ground Beef Casserole

Some evenings, I just want a warm, cheesy dinner that tastes like comfort food without leaving me with a mountain of dishes. That’s exactly why I love this Low Carb Ground Beef Casserole. It’s hearty, savory, packed with flavor, and topped with a delicious layer of melted cheese.

I first started appreciating casseroles like this when I wanted an easy dinner the whole family could enjoy. Ground beef, garlic, tender vegetables, and plenty of cheese make such a satisfying combination. It’s the kind of meal I’d happily prepare on a busy weeknight, and leftovers make lunch the next day even easier!

Why You’ll Love This Recipe

• Low-carb comfort food: No pasta, rice, or potatoes required.
• Cheesy and satisfying: Melted cheddar and mozzarella create a delicious topping.
• Family-friendly: A simple, familiar dinner that everyone can customize.
• Easy meal prep: Assemble it ahead of time and bake when needed.
• One-pan filling: Cook the beef and vegetables in one skillet before transferring everything to a baking dish.

Ingredients

• 1½ lb lean ground beef
• 1 tbsp olive oil, if needed
• ½ medium onion, finely chopped
• 3 garlic cloves, minced
• 1 medium zucchini, diced
• 1 cup sliced mushrooms
• 1 cup chopped bell pepper
• 1 cup tomato sauce with no added sugar
• ½ cup sour cream
• 1 tsp Italian seasoning
• ½ tsp paprika
• ½ tsp onion powder
• Salt and black pepper, to taste
• 1 cup shredded cheddar cheese
• 1 cup shredded mozzarella cheese
• 2 tbsp grated Parmesan cheese
• 2 tbsp fresh parsley, chopped

Instructions

Step 1: Preheat the Oven

Preheat your oven to 375°F (190°C). Lightly grease a 9-by-13-inch baking dish or a similar-sized casserole dish.

Step 2: Brown the Ground Beef

Place a large skillet over medium-high heat. Add the ground beef and cook for 6–8 minutes, breaking it into small pieces as it browns.

Drain excess grease if necessary. Add the chopped onion and cook for another 3 minutes, until softened.

Step 3: Add the Vegetables

Stir in the minced garlic, zucchini, mushrooms, and bell pepper. Cook for 4–5 minutes, stirring occasionally, until the vegetables begin to soften and most excess moisture has evaporated.

Step 4: Season the Mixture

Add the tomato sauce, Italian seasoning, paprika, onion powder, salt, and black pepper. Stir well and simmer for 2–3 minutes.

Remove the skillet from the heat and gently mix in the sour cream. This adds creaminess and balances the savory tomato flavor.

Step 5: Assemble the Casserole

Transfer the beef mixture to the prepared baking dish and spread it evenly.

Sprinkle the cheddar and mozzarella over the top, followed by the Parmesan cheese.

Step 6: Bake Until Golden

Bake uncovered for 15–20 minutes, or until the cheese is melted and bubbling around the edges.

For a more golden top, broil for 1–2 minutes, watching carefully to prevent burning.

Step 7: Rest and Serve

Let the casserole rest for 5–10 minutes before serving. Sprinkle with fresh parsley and enjoy while warm.

My Tips for the Best Casserole

• Choose lean beef: Ground beef with around 85–90% lean meat gives good flavor without excessive grease.
• Cook off excess moisture: Zucchini and mushrooms release water, so sauté them before baking to avoid a watery casserole.
• Grate your own cheese: Freshly grated cheese often melts more smoothly than pre-shredded varieties.
• Check your tomato sauce: Choose one with no added sugar and check the carbohydrate content on the label.
• Let it rest: A short resting period helps the casserole hold together when served.

Easy Variations

Creamy Beef Casserole: Replace the tomato sauce with ½ cup beef broth and ½ cup cream cheese, softened. Add a little extra Italian seasoning.

Taco-Style Casserole: Swap the Italian seasoning for taco seasoning and use cheddar, Monterey Jack, and a few sliced jalapeños.

Broccoli and Beef: Replace the bell pepper with steamed broccoli florets for a different vegetable combination.

Spicy Version: Add red pepper flakes or diced jalapeños to the beef mixture.

Dairy-Free Option: Use unsweetened dairy-free sour cream and suitable dairy-free shredded cheese.

What to Serve With It

This casserole is satisfying on its own, but you can pair it with:

• Garlic-roasted broccoli
• Cauliflower rice
• A fresh cucumber and tomato salad
• Roasted green beans
• Cauliflower mash
• Simple leafy greens with olive oil and lemon

For an easy low-carb dinner, I especially like the idea of serving a warm slice with a crisp green salad.

Make-Ahead and Storage

Make ahead: Prepare the beef and vegetable mixture, transfer it to the baking dish, and add the cheese. Cover and refrigerate for up to 24 hours. Bake until the center is hot and the cheese is bubbling; allow extra time if baking straight from the refrigerator.

Refrigerate: Store leftovers in an airtight container for 3–4 days.

Freeze: Freeze in individual portions for up to 2–3 months for best quality. Thaw overnight in the refrigerator before reheating.

Reheat: Warm individual portions in the microwave or cover the casserole and reheat in a 350°F (175°C) oven until heated through.

Recipe Details

• Prep Time: 15 minutes
• Cook Time: 30 minutes
• Total Time: 45 minutes
• Servings: 6

Approximate Nutrition Per Serving

• Calories: 420
• Protein: 32g
• Carbohydrates: 9g
• Fiber: 2g
• Net Carbs: 7g
• Fat: 29g

Nutrition is estimated and varies depending on the ground beef, cheese, tomato sauce, and portion size. Check product labels for the most accurate carbohydrate count.

Frequently Asked Questions

Is this casserole suitable for a low-carb diet?

Yes. It contains no pasta, rice, or potatoes and uses lower-carbohydrate vegetables. The exact carbohydrate content depends on your ingredients and serving size.

Can I use ground turkey instead of beef?

Absolutely. Ground turkey works well, although the casserole may have a slightly lighter flavor. Add a little olive oil if the meat is very lean.

How can I prevent a watery casserole?

Cook the vegetables until excess moisture evaporates before adding the mixture to the baking dish. Avoid adding too much tomato sauce, and drain the beef if needed.

Can I make this casserole without tomato sauce?

Yes. Use a mixture of beef broth and softened cream cheese for a creamy, tomato-free version.

Is this recipe diabetic-friendly?

It may fit into some diabetes meal plans because it is relatively low in carbohydrates and provides protein. However, individual needs vary, and the total carbohydrate content should be checked against your personal meal plan.