Keto Chicken Alfredo Casserole – Creamy, Comforting, and Low-Carb

This Keto Chicken Alfredo Casserole checks all the boxes: creamy, cheesy, ultra-satisfying, and still low in carbs. It’s the kind of weeknight dinner that feels cozy but doesn’t weigh you down. With tender chicken, a rich Alfredo sauce, and a veggie base that stands in for pasta, it’s comfort food made smarter.

You can prep it ahead, bake it when you’re ready, and serve it to both keto eaters and non-keto friends—no one will miss the noodles.

Keto Chicken Alfredo Casserole - Creamy, Comforting, and Low-Carb

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Prep Time 15 minutes mins

Cook Time 30 minutes mins

Total Time 45 minutes mins

Servings 6 servings

Ingredients

  

• 3 cups cooked chicken, shredded or cubed (rotisserie works great)
• 1 large head of cauliflower, cut into small florets (about 5–6 cups) or 4 cups broccoli florets
• 2 tablespoons butter
• 3 cloves garlic, minced
• 1 1/2 cups heavy cream
• 4 ounces cream cheese, softened and cubed
• 1 cup grated Parmesan cheese (plus more for topping)
• 1 cup shredded mozzarella (for topping)
• 1/4 teaspoon nutmeg (optional but classic in Alfredo)
• 1/2 teaspoon onion powder
• 1/2 teaspoon Italian seasoning (or dried parsley + oregano)
• Salt and black pepper, to taste
• 2 tablespoons olive oil (for roasting the cauliflower)
• Fresh parsley, chopped, for garnish (optional)

Instructions

 

• Preheat and prep: Heat the oven to 400°F (200°C). Grease a 9x13-inch baking dish. Line a sheet pan with parchment.
• Roast the cauliflower: Toss florets with olive oil, salt, and pepper. Spread on the sheet pan and roast for 18–22 minutes, until fork-tender with a little color. This keeps the casserole from getting watery.
• Warm the chicken: If using cold, cooked chicken, chop or shred it now. Set aside in a large bowl.
• Make the Alfredo sauce: In a medium saucepan over medium heat, melt butter. Add garlic and cook 30–60 seconds, until fragrant. Pour in heavy cream and bring to a gentle simmer.
• Thicken and season: Add cream cheese and whisk until smooth. Stir in Parmesan, nutmeg, onion powder, Italian seasoning, salt, and pepper. Simmer 2–3 minutes until thick and silky. Taste and adjust seasoning.
• Combine: Add roasted cauliflower and chicken to the large bowl. Pour the Alfredo sauce over the top and toss to coat evenly.
• Assemble: Transfer the mixture to the prepared baking dish. Sprinkle mozzarella and a bit more Parmesan over the surface.
• Bake: Reduce oven to 375°F (190°C). Bake for 15–20 minutes, until the cheese is melted and bubbling around the edges.
• Broil for color (optional): Broil 1–2 minutes to brown the top. Watch closely.
• Finish and serve: Let it rest 5–10 minutes to set. Sprinkle with chopped parsley and serve warm.

What Makes This Recipe So Good

• All the flavor, fewer carbs: You get the creamy Alfredo experience without pasta, thanks to low-carb vegetables and a rich sauce.
• Weeknight-friendly: Uses cooked chicken and a simple stovetop sauce, then bakes quickly for a golden, bubbly finish.
• Meal-prep ready: Assemble it ahead and refrigerate or freeze. It reheats well for easy lunches or busy nights.
• Balanced and filling: High in protein and healthy fats, so it keeps you satisfied without spiking carbs.
• Customizable: Switch up the veggies, add bacon or spinach, or use rotisserie chicken to save time.

Ingredients

• 3 cups cooked chicken, shredded or cubed (rotisserie works great)
• 1 large head of cauliflower, cut into small florets (about 5–6 cups) or 4 cups broccoli florets
• 2 tablespoons butter
• 3 cloves garlic, minced
• 1 1/2 cups heavy cream
• 4 ounces cream cheese, softened and cubed
• 1 cup grated Parmesan cheese (plus more for topping)
• 1 cup shredded mozzarella (for topping)
• 1/4 teaspoon nutmeg (optional but classic in Alfredo)
• 1/2 teaspoon onion powder
• 1/2 teaspoon Italian seasoning (or dried parsley + oregano)
• Salt and black pepper, to taste
• 2 tablespoons olive oil (for roasting the cauliflower)
• Fresh parsley, chopped, for garnish (optional)

How to Make It

1. Preheat and prep: Heat the oven to 400°F (200°C). Grease a 9×13-inch baking dish.

   Line a sheet pan with parchment.

2. Roast the cauliflower: Toss florets with olive oil, salt, and pepper. Spread on the sheet pan and roast for 18–22 minutes, until fork-tender with a little color. This keeps the casserole from getting watery.
3. Warm the chicken: If using cold, cooked chicken, chop or shred it now.

   Set aside in a large bowl.

4. Make the Alfredo sauce: In a medium saucepan over medium heat, melt butter. Add garlic and cook 30–60 seconds, until fragrant. Pour in heavy cream and bring to a gentle simmer.
5. Thicken and season: Add cream cheese and whisk until smooth.

   Stir in Parmesan, nutmeg, onion powder, Italian seasoning, salt, and pepper. Simmer 2–3 minutes until thick and silky. Taste and adjust seasoning.

6. Combine: Add roasted cauliflower and chicken to the large bowl.

   Pour the Alfredo sauce over the top and toss to coat evenly.

7. Assemble: Transfer the mixture to the prepared baking dish. Sprinkle mozzarella and a bit more Parmesan over the surface.
8. Bake: Reduce oven to 375°F (190°C). Bake for 15–20 minutes, until the cheese is melted and bubbling around the edges.
9. Broil for color (optional): Broil 1–2 minutes to brown the top.

   Watch closely.

10. Finish and serve: Let it rest 5–10 minutes to set. Sprinkle with chopped parsley and serve warm.

Storage Instructions

• Refrigerator: Cool completely, then cover and store for up to 4 days.
• Freezer: Wrap tightly and freeze up to 2 months. For best texture, freeze before baking.
• Reheating: Reheat covered at 350°F (175°C) for 15–20 minutes, or microwave individual portions in 60–90 second bursts.

  Add a splash of cream if it looks dry.

• Make-ahead: Assemble up to the baking step, cover, and refrigerate up to 24 hours. Bake as directed, adding a few extra minutes if cold.

Benefits of This Recipe

• Keto-friendly: Low in carbs, with fat and protein to support a ketogenic lifestyle.
• Great use of leftovers: Rotisserie or leftover chicken makes this fast and economical.
• Family-approved: Creamy, cheesy flavors appeal to picky eaters.
• Gluten-free: No pasta or flour-based thickeners required.
• Flexible base: Swap veggies or add-ins without losing the core flavor.

Pitfalls to Watch Out For

• Watery casserole: Skipping the roast can lead to excess moisture. Roast the veggies until lightly browned and let them steam off briefly before mixing.
• Over-salting: Parmesan is salty.

  Season the sauce gradually and taste as you go.

• Broken sauce: Boiling too hard can cause separation. Keep it at a gentle simmer and whisk until smooth.
• Rubbery chicken: Use cooked chicken added at the end. Don’t bake too long after assembling.
• Flat flavor: Don’t skip garlic, nutmeg, and pepper.

  They bring classic Alfredo depth.

Recipe Variations

• Broccoli Alfredo: Swap cauliflower for broccoli florets. Roast slightly less time to keep them crisp-tender.
• Bacon and Spinach: Cook 4–6 slices of bacon until crisp. Crumble and add with 2 cups fresh spinach wilted in the bacon fat.
• Mushroom Upgrade: Sauté 8 ounces sliced mushrooms in butter until browned and add to the mix for a steakhouse vibe.
• Pesto Alfredo: Stir 2 tablespoons of basil pesto into the sauce for a fresh, herby twist.
• Spicy Kick: Add red pepper flakes or a pinch of cayenne to the sauce.
• Dairy Tweaks: Replace part of the heavy cream with unsweetened almond milk and simmer a bit longer to thicken.
• Different Cheeses: Try Gruyère or Asiago on top for a nuttier flavor.

FAQ

Can I use frozen cauliflower?

Yes, but roast it from frozen on a hot sheet pan to evaporate moisture.

Expect a few extra minutes in the oven and pat it dry if needed before mixing.

What can I substitute for heavy cream?

For keto, stick with heavy cream for the best texture. If you must lighten it, use half heavy cream and half unsweetened almond milk, then simmer a bit longer to thicken.

Is rotisserie chicken okay?

Absolutely. It’s a time-saver and adds great flavor.

Remove the skin if you prefer a smoother texture in the casserole.

How do I make it even lower in carbs?

Use cauliflower over broccoli, keep the sauce thick (no extra liquid), and avoid add-ins like onions or tomato. Portion control also helps keep carbs in check.

Can I prepare this dairy-free?

Traditional Alfredo relies on dairy, but you can experiment with full-fat coconut milk, dairy-free cream cheese, and nutritional yeast. Flavor will differ, but it can still be tasty.

How do I keep leftovers from drying out?

Reheat gently and add a splash of cream or chicken broth.

Covering the dish while reheating helps lock in moisture.

What should I serve with it?

A crisp green salad with a simple vinaigrette, roasted asparagus, or sautéed zucchini works well. Keep sides light and low-carb to stay keto-friendly.

Wrapping Up

Keto Chicken Alfredo Casserole is a simple way to bring creamy comfort to your table without the carbs. It’s easy to customize, easy to prep, and just as good for leftovers.

Whether you’re cooking for a crowd or stocking the fridge for the week, this casserole delivers cozy flavor and dependable results. Keep it in your dinner rotation and tweak the add-ins to make it your own.