Ground Beef Cauliflower Casserole

The first time I made this casserole, my husband asked three times if I was sure there was no pasta in it. That's how satisfying and hearty this cauliflower rice version turns out.

I started making this during busy weeknights when I wanted something that felt like a hug in a dish but wouldn't leave me feeling heavy. My sister-in-law now requests it every time she visits.

Ingredients

• 1 lb lean ground beef: Ground turkey works beautifully too if you prefer something lighter
• 1 medium onion: Finely chopped so it melts into the background sweetness
• 3 cloves garlic: Freshly minced makes all the difference here
• 4 cups cauliflower rice: Fresh gives better texture but frozen is perfectly fine in a pinch
• 1 medium red bell pepper: Adds little bursts of sweetness and color
• 1 cup baby spinach: Optional but I love the extra nutrition and color
• 1 cup sour cream: Full fat creates the creamiest results
• 1 cup shredded cheddar: Reserve half for the filling and half for that golden topping
• 1/2 cup shredded mozzarella: For the classic cheese pull effect
• 2 tbsp olive oil: Helps vegetables soften nicely
• 1 tsp dried oregano: Woodsy notes that ground beef loves
• 1 tsp dried basil: Brightens up the rich flavors
• 1/2 tsp smoked paprika: My secret ingredient for depth
• 1/2 tsp salt and black pepper: Adjust to your taste preferences
• 1/4 tsp crushed red pepper flakes: Just a gentle warmth if you like
• 2 tbsp fresh parsley: Adds a fresh finish against all that rich cheese

Instructions

Preheat your oven to 375°F:

While it heats up, grab your largest skillet and 9x13 baking dish

Sauté the vegetables:

Cook onion and red bell pepper in olive oil for 3-4 minutes until they soften and smell sweet

Add the garlic:

Throw it in for just 1 minute, stirring constantly so it does not burn

Brown the beef:

Add ground beef and break it apart with your spatula, cooking 5-7 minutes until no pink remains

Season the meat:

Stir in oregano, basil, smoked paprika, salt, pepper and red pepper flakes until everything smells fragrant

Add cauliflower and spinach:

Cook 4-5 minutes until cauliflower is tender and any excess liquid has cooked off

Make it creamy:

Remove from heat and fold in sour cream with half the cheddar until well combined

Transfer to baking dish:

Spread everything evenly into your greased 9x13 dish

Add the cheese topping:

Sprinkle remaining cheddar and all the mozzarella over the top

Bake until bubbly:

20 minutes in the oven until the cheese is melted and golden brown in spots

Rest and serve:

Let it sit for 5 minutes so it sets up nicely, then garnish with parsley

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This recipe became my go-to when my friend started a low carb diet and was missing comfort food. We ate it on her back porch and she literally said she forgot she was eating healthy.

Making It Your Own

I have swapped ground turkey for beef plenty of times when I want something lighter. Mushrooms and zucchini also work beautifully added in with the cauliflower.

Perfect Pairings

A crisp green salad with vinaigrette cuts through all the richness nicely. Sometimes I roast extra vegetables on the side sheet pan while the casserole bakes.

Storage And Reheating

This keeps beautifully in the refrigerator for up to four days. I actually think the flavors get better after a night melding together.

• Reheat individual portions in the microwave for 2 minutes
• Cover the dish with foil and warm at 350°F for larger portions
• Freeze portions for up to three months if you want meal prep ready to go

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Hope this becomes one of those recipes you turn to without even thinking. That is how it happened in my kitchen anyway.

Recipe FAQs

→ Can I use frozen cauliflower rice?

Yes, frozen cauliflower rice works perfectly in this dish. Simply add it directly to the skillet without thawing, and cook until tender and any excess liquid has evaporated.

→ How do I store leftovers?

Store cooled portions in an airtight container in the refrigerator for up to 4 days. Reheat in the microwave or oven until warmed through.

→ Can I make this ahead of time?

Absolutely. Assemble the dish up to step 8, cover tightly, and refrigerate for up to 24 hours before baking. You may need to add 5-10 minutes to the baking time.

→ What can I substitute for ground beef?

Ground turkey, chicken, or even plant-based crumbles work well as alternatives. Adjust cooking time slightly as leaner meats may cook faster.

→ Is this dish freezer-friendly?

Yes, you can freeze the assembled, unbaked dish for up to 3 months. Thaw overnight in the refrigerator before baking as directed.