Keto Stuffed Pepper Casserole

Forget the fuss of hollowing and stuffing individual peppers! This Keto Stuffed Pepper Casserole delivers all the beloved flavors of the classic dish in one hearty, satisfying bake. It’s the ultimate weeknight solution—deconstructed, easy to make, and perfect for meal prep. With a rich, savory filling of ground beef, cauliflower rice, melted cheeses, and classic seasonings, all topped with tender bell peppers, this casserole is low-carb comfort food at its finest. Your family won’t believe it’s keto!

Why You’ll Love This Recipe

One-Pan Wonder: Minimal dishes, maximum flavor.
Meal Prep Hero: Tastes even better as leftovers, making lunches a breeze.
Customizable: Swap the protein, cheese, or veggies to suit your taste.
Crowd-Pleaser: So delicious, no one will guess it’s diet-friendly.

Nutrition Information (Per Serving)

Calories: 485
Total Fat: 36g
Saturated Fat: 15g
Cholesterol: 115mg
Sodium: 780mg
Total Carbohydrates: 9g
Dietary Fiber: 3g
Net Carbs: 6g
Protein: 30g

Nutritional values are estimates based on the ingredients used and may vary with specific brands or substitutions.

Ingredients

For the Casserole Base:

1.5 lbs (680g) ground beef (85/15 lean-to-fat ratio recommended)
1 tablespoon olive oil or avocado oil
1 medium yellow onion, diced
3 cloves garlic, minced
1 (12 oz) bag riced cauliflower (fresh or frozen, thawed)*
1 (14.5 oz) can diced tomatoes, undrained
1 (8 oz) can tomato sauce
2 tablespoons tomato paste
1 tablespoon Worcestershire sauce (check for sugar-free if strict keto)
2 teaspoons Italian seasoning
1 teaspoon smoked paprika
1 teaspoon sea salt
½ teaspoon black pepper

For the Veggie Layer & Topping:

2 large bell peppers (1 red, 1 green), cut into 1-inch chunks
1.5 cups shredded mozzarella cheese, divided
1 cup shredded cheddar cheese, divided
¼ cup grated Parmesan cheese
Fresh parsley or basil, chopped (for garnish)

Equipment Needed

Large, oven-safe skillet (like cast iron) or a sauté pan + 9×13 inch casserole dish
Cutting board & sharp knife
Measuring cups and spoons
Wooden spoon or spatula
Aluminum foil

Step-by-Step Instructions

Step 1: Preheat & Prep
Preheat your oven to 375°F (190°C). Dice the onion, mince the garlic, and cut the bell peppers into uniform chunks. Set aside. If using frozen riced cauliflower, ensure it is thawed and squeezed in a clean kitchen towel to remove excess moisture—this is key to avoiding a soggy casserole.

Step 2: Brown the Beef
Heat the oil in your large skillet over medium-high heat. Add the ground beef, breaking it apart with a spoon. Cook until no longer pink, about 7-8 minutes. Do not drain the fat (this adds flavor and moisture for keto). If using a separate pan, transfer the browned beef to your 9×13 casserole dish.

Step 3: Sauté the Aromatics
In the same skillet with the beef (or in the pan if you used one), add the diced onion. Sauté for 3-4 minutes until softened. Add the minced garlic and cook for another minute until fragrant.

Step 4: Build the Flavor Base
To the skillet, add the riced cauliflower, diced tomatoes (with juices), tomato sauce, tomato paste, Worcestershire sauce, Italian seasoning, smoked paprika, salt, and pepper. Stir thoroughly to combine. Reduce heat to medium and let the mixture simmer for 5-7 minutes, allowing the flavors to meld and the cauliflower to soften slightly.

Step 5: Assemble the Casserole
If you used an oven-safe skillet, you can assemble directly in it. If not, transfer the entire meat mixture to your greased 9×13 casserole dish. Fold in half of the mozzarella (¾ cup) and half of the cheddar (½ cup) into the hot mixture until evenly distributed. This creates a wonderfully cheesy base. Evenly scatter the bell pepper chunks over the top, pressing them gently into the mixture.

Step 6: Add the Final Cheese Layer
Sprinkle the remaining mozzarella and cheddar cheeses over the peppers. Finish with the grated Parmesan cheese, which will create a beautifully golden crust.

Step 7: Bake to Perfection
Cover the dish (or skillet) loosely with aluminum foil. Bake for 20 minutes. Then, remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and starting to brown, and the peppers are tender-crisp.

Step 8: Rest & Serve
Remove the casserole from the oven and let it rest for 5-10 minutes. This allows the flavors to settle and makes it easier to slice. Garnish with fresh chopped parsley or basil. Serve hot and enjoy!

Pro Tips for Success

Avoid Sogginess: Draining the diced tomatoes is an option for a thicker result, but we find the juice adds flavor. The crucial step is removing water from the cauliflower rice.
Boost the Flavor: Brown the beef in batches for better browning (the Maillard reaction!). Add a pinch of red pepper flakes for heat.
Test for Doneness: The peppers should be pierceable with a fork but still have a slight bite (al dente) for the best texture.
Make it Your Own: Substitute ground Italian sausage for half the beef. Add sliced mushrooms with the onions. Try a Mexican twist with taco seasoning and pepper jack cheese.

Storage & Reheating Instructions

Refrigerator: Store cooled leftovers in an airtight container for up to 4 days.
Freezer: This casserole freezes beautifully! Portion it, wrap tightly, and freeze for up to 3 months. Thaw overnight in the fridge before reheating.
Reheating: Reheat individual portions in the microwave for 1-2 minutes. For larger portions, reheat, covered, in a 350°F oven for 15-20 minutes until heated through.

Frequently Asked Questions (FAQ)

Can I use real rice instead of cauliflower rice?
Using white or brown rice will significantly increase the carb count, making it non-keto. For a low-carb dish, cauliflower rice is essential.

Is this recipe spicy?
Not as written. The smoked paprika adds depth, not heat. For a spicy kick, add ¼ teaspoon of cayenne pepper or a diced jalapeño with the bell peppers.

Can I make this ahead of time?
Absolutely! Assemble the casserole completely (through Step 6), cover, and refrigerate for up to 24 hours. Add 5-10 minutes to the baking time when cooking from cold.

What can I serve with this casserole?
Keep it keto with a simple side salad with a vinaigrette, roasted asparagus, or creamy garlic spinach. For non-keto guests, a side of crusty bread is perfect for soaking up the sauce.

Recipe Card Key: gluten-free, grain-free, sugar-free, high-protein
Last Updated: October 26, 2023

Enjoy your delicious, hassle-free Keto Stuffed Pepper Casserole—a guaranteed hit that brings comfort to your low-carb table without the carb coma!