Keto Broccoli Cauliflower Casserole – Creamy, Cheesy, and Low-Carb Comfort

This Keto Broccoli Cauliflower Casserole brings cozy comfort without the carb crash. It’s rich, creamy, and cheesy, with tender veggies baked under a golden, bubbly top. You can serve it as a hearty side or a satisfying main with added protein.

The prep is simple, and it works for weeknights, potlucks, or holiday tables alike. If you love a classic casserole vibe but want to keep things keto, this one’s a keeper.

Keto Broccoli Cauliflower Casserole - Creamy, Cheesy, and Low-Carb Comfort

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Prep Time 15 minutes mins

Cook Time 30 minutes mins

Total Time 45 minutes mins

Servings: 6 servings

Ingredients Method

Ingredients

  

• Broccoli florets – Fresh or frozen. Fresh gives the best texture.
• Cauliflower florets – Pairs perfectly with broccoli and soaks up the sauce.
• Cream cheese – Softened, for a smooth sauce.
• Heavy cream – Adds richness and keeps it keto.
• Shredded cheddar cheese – Sharp cheddar gives bold flavor.
• Shredded mozzarella – Melts beautifully for that stretchy top.
• Grated Parmesan – For savory depth and a golden finish.
• Butter – Helps sauté and rounds out the sauce.
• Garlic – Freshly minced for best flavor.
• Onion powder – Adds sweetness without the carbs of a full onion.
• Dijon mustard – A small amount brightens the sauce.
• Smoked paprika – Optional, for a hint of warmth.
• Salt and black pepper – To taste.
• Crushed red pepper flakes – Optional, for a little heat.
• Chopped bacon – Optional, for smoky crunch.
• Fresh chives or parsley – For garnish.

Method

 

1. Preheat the oven: Set to 375°F (190°C). Grease a 9x13-inch baking dish or similar casserole dish.
2. Prep the veggies: Cut broccoli and cauliflower into bite-sized florets. You’ll want roughly 4 cups of each.
3. Par-cook the florets: Steam or blanch for 3–4 minutes until just tender but still crisp. Drain well and pat dry to avoid watery casserole.
4. Sauté aromatics: In a large skillet over medium heat, melt 2 tablespoons butter. Add garlic and cook 30–60 seconds until fragrant.
5. Make the sauce: Lower heat and whisk in 6 ounces softened cream cheese until smooth. Slowly pour in 1 cup heavy cream, whisking to combine. Stir in 1 cup shredded cheddar, 1/2 cup mozzarella, and 1/4 cup Parmesan. Add 1 teaspoon Dijon, 1/2 teaspoon onion powder, 1/2 teaspoon smoked paprika, and a pinch of red pepper flakes if using. Season with salt and pepper.
6. Taste and adjust: The sauce should be well-seasoned and slightly thick. If too thick, add a splash of cream.
7. Combine: Add the drained broccoli and cauliflower to the skillet, stirring to coat every piece. If your skillet is small, mix in a large bowl instead.
8. Assemble: Transfer to your prepared baking dish. Top with remaining 1/2 cup cheddar, 1/2 cup mozzarella, and 2–3 tablespoons Parmesan. Sprinkle cooked, chopped bacon on top if using.
9. Bake: Bake for 18–22 minutes, until the top is bubbling and lightly browned. For extra color, broil for 1–2 minutes at the end.
10. Rest and garnish: Let it sit 5–10 minutes to set. Finish with chopped chives or parsley.

What Makes This Recipe So Good

• Perfectly creamy and cheesy: A velvety sauce coats every bite without feeling heavy or greasy.
• Low-carb and keto-friendly: Broccoli and cauliflower add fiber with minimal net carbs.
• Flexible: Add bacon, chicken, or a different cheese to make it your own.
• Meal-prep friendly: Holds up well in the fridge and reheats beautifully.
• Family-approved: Even picky eaters enjoy the creamy texture and cheesy top.

What You’ll Need

• Broccoli florets – Fresh or frozen. Fresh gives the best texture.
• Cauliflower florets – Pairs perfectly with broccoli and soaks up the sauce.
• Cream cheese – Softened, for a smooth sauce.
• Heavy cream – Adds richness and keeps it keto.
• Shredded cheddar cheese – Sharp cheddar gives bold flavor.
• Shredded mozzarella – Melts beautifully for that stretchy top.
• Grated Parmesan – For savory depth and a golden finish.
• Butter – Helps sauté and rounds out the sauce.
• Garlic – Freshly minced for best flavor.
• Onion powder – Adds sweetness without the carbs of a full onion.
• Dijon mustard – A small amount brightens the sauce.
• Smoked paprika – Optional, for a hint of warmth.
• Salt and black pepper – To taste.
• Crushed red pepper flakes – Optional, for a little heat.
• Chopped bacon – Optional, for smoky crunch.
• Fresh chives or parsley – For garnish.

How to Make It

1. Preheat the oven: Set to 375°F (190°C).
   

   Grease a 9×13-inch baking dish or similar casserole dish.

2. Prep the veggies: Cut broccoli and cauliflower into bite-sized florets. You’ll want roughly 4 cups of each.
3. Par-cook the florets: Steam or blanch for 3–4 minutes until just tender but still crisp. Drain well and pat dry to avoid watery casserole.
4. Sauté aromatics: In a large skillet over medium heat, melt 2 tablespoons butter.
   

   Add garlic and cook 30–60 seconds until fragrant.

5. Make the sauce: Lower heat and whisk in 6 ounces softened cream cheese until smooth. Slowly pour in 1 cup heavy cream, whisking to combine. Stir in 1 cup shredded cheddar, 1/2 cup mozzarella, and 1/4 cup Parmesan.
   

   Add 1 teaspoon Dijon, 1/2 teaspoon onion powder, 1/2 teaspoon smoked paprika, and a pinch of red pepper flakes if using. Season with salt and pepper.

6. Taste and adjust: The sauce should be well-seasoned and slightly thick. If too thick, add a splash of cream.
7. Combine: Add the drained broccoli and cauliflower to the skillet, stirring to coat every piece.
   

   If your skillet is small, mix in a large bowl instead.

8. Assemble: Transfer to your prepared baking dish. Top with remaining 1/2 cup cheddar, 1/2 cup mozzarella, and 2–3 tablespoons Parmesan. Sprinkle cooked, chopped bacon on top if using.
9. Bake: Bake for 18–22 minutes, until the top is bubbling and lightly browned.
   

   For extra color, broil for 1–2 minutes at the end.

10. Rest and garnish: Let it sit 5–10 minutes to set. Finish with chopped chives or parsley.

Storage Instructions

• Refrigerator: Cool completely, then cover and refrigerate for up to 4 days.
• Freezer: Freeze in an airtight, freezer-safe container for up to 2 months. Thaw overnight in the fridge before reheating.
• Reheating: Warm in a 325°F (165°C) oven until heated through, about 15–20 minutes.
  

  For single servings, microwave at 50–70% power in short bursts, stirring in between.

Benefits of This Recipe

• Low in carbs, high in satisfaction: Rich sauce and fiber-filled veggies keep you full longer.
• Great for gluten-free eaters: No flour or breadcrumbs needed.
• Balanced texture: Tender veggies, creamy sauce, and a lightly crisp top.
• Versatile serving options: Works as a side with steak or chicken, or as a main with added protein.
• Easy to scale: Double for a crowd or halve for smaller portions.

Pitfalls to Watch Out For

• Watery casserole: Overcooked or wet florets release moisture. Par-cook briefly and drain well. Pat dry if needed.
• Grainy sauce: Add cheese over low heat and whisk gently.
  

  High heat can cause separation.

• Under-seasoning: Taste the sauce before baking. Broccoli and cauliflower need enough salt to shine.
• Overbaking: Too long in the oven can make the vegetables mushy. Pull it when it’s bubbling and lightly browned.

Alternatives

• Cheese swaps: Try Gruyère, gouda, fontina, or pepper jack for different flavor profiles.
• Dairy-light version: Swap some heavy cream with unsweetened almond milk and add a pinch of xanthan gum to thicken.
  

  Use less cheese on top.

• Add protein: Stir in cooked chicken, turkey, sausage, or crumbled bacon for a full meal.
• Veggie variations: Add sautéed mushrooms or spinach. Keep an eye on moisture and cook off extra liquid first.
• Topping ideas: Mix crushed pork rinds with Parmesan for a crunchy keto topping.

FAQ

Can I use frozen broccoli and cauliflower?

Yes. Thaw completely and drain well, then pat dry.

Skip or shorten the par-cook step, since frozen vegetables are already partially cooked.

How do I make it less rich but still creamy?

Use half heavy cream and half unsweetened almond milk. Add 1/8 teaspoon xanthan gum to thicken if needed. Keep the cheese amounts the same for flavor.

Is this casserole gluten-free?

Yes, as written it’s gluten-free.

Always check labels on cream cheese, mustard, and spices to be safe.

Can I make this ahead?

Absolutely. Assemble up to the baking step, cover, and refrigerate for up to 24 hours. Add 5–10 minutes to the bake time if going straight from the fridge.

How do I keep the sauce from separating?

Melt cheese over low heat and avoid boiling the sauce.

Whisk slowly, and add the cream gradually so it emulsifies with the cream cheese.

What should I serve with it?

It pairs well with roasted chicken, grilled steak, or baked salmon. A crisp green salad balances the richness.

How many carbs are in a serving?

Exact numbers vary by brands and portions, but a typical serving is around 5–7g net carbs. Use your favorite nutrition calculator for precise macros.

Wrapping Up

This Keto Broccoli Cauliflower Casserole is all about comfort made simple. It’s creamy, cheesy, and full of flavor, with a texture that holds up well for leftovers. Keep it classic or play with add-ins to fit your weeknight or weekend plans. If you’re looking for a reliable low-carb side that feels like a treat, this one belongs in your rotation. Enjoy it hot, bubbly, and straight from the oven.