Easy Low Carb Chicken Casserole

This easy low carb chicken casserole has become my go-to when I need a quick, comforting, and satisfying dinner that doesn’t derail my low-carb goals. It’s cheesy, rich, and loaded with protein, yet it skips the pasta and grains completely. I love that it uses ingredients I often already have on hand, and I can get it in the oven in less than 20 minutes.

Whether I’m following a keto lifestyle or just trying to keep dinners a bit lighter, this dish fits right in – and even the picky eaters at my table don’t complain. In fact, they usually ask for seconds.

Why You’ll Love This Recipe

• Keto-friendly meal – I don’t use any pasta or grains, so it fits perfectly into a low-carb or keto plan.

• Protein-packed – The hearty chicken and cheese combo keeps me full and satisfied.

• Veggie-rich – With spinach or broccoli tucked inside, it’s a sneaky way to get in more greens.

• Time-saving prep – Using pre-cooked chicken means I can throw this together in minutes.

• Make-ahead friendly – I love that I can prep it earlier in the day and bake it later when I’m ready.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

For the casserole:
4 cups diced or shredded cooked chicken breast
5 cups broccoli florets OR 1 pound thawed frozen spinach (well-drained)
3 cloves minced garlic
1 cup ranch dressing
1/2 cup shredded mozzarella cheese
1/2 cup shredded cheddar cheese

For the topping:
1/2 cup shredded mozzarella cheese
1/2 cup shredded cheddar cheese

Optional:
1–3 teaspoons ranch seasoning mix (for added flavor)

Directions

Step 1: Prepare Vegetables
I preheat the oven to 375°F (191°C). If I’m using frozen spinach, I make sure it’s completely thawed and squeeze out every bit of water. For fresh broccoli, I blanch it for just 1–2 minutes until bright green, then drain it well.

Step 2: Combine the Main Ingredients
In a large mixing bowl, I combine the cooked chicken, garlic, prepared veggies, ranch dressing, and half of each cheese (mozzarella and cheddar). If I want a bit more flavor, I’ll add some ranch seasoning too. Sometimes, I mix everything right in the casserole dish to save on dishes.

Step 3: Transfer to Casserole Dish
I pour the mixture into a 9×13 inch (23×33 cm) baking dish and spread it out evenly.

Step 4: Add the Cheese Topping
I sprinkle the remaining mozzarella and cheddar cheeses on top for that golden, bubbly finish.

Step 5: Bake and Serve
I bake it for about 15 minutes, just until everything is hot and the cheese is beautifully melted. I let it cool slightly before serving.

Servings and Timing

Servings: 6
Preparation Time: 15–20 minutes
Cooking Time: 15–20 minutes
Total Time: 30–40 minutes
Level of Difficulty: Easy

Variations

• I sometimes swap chicken breast for chicken thighs if I want something more tender.

• For a different cheese flavor, I like Monterey Jack, provolone, or Colby.

• Not a fan of ranch? I’ve used a mix of mayo and sour cream with Italian seasoning.

• I’ve also made it with cauliflower florets or even chopped Brussels sprouts instead of broccoli or spinach.

• Fresh spinach works great too—I just cook it down first and drain it well.

Storage/Reheating

To store leftovers, I transfer them into an airtight container and refrigerate for up to 3 days.

When I reheat it, I usually use the microwave for a quick lunch – about 1–2 minutes per serving. If I’m reheating a larger portion, I cover it with foil and warm it in the oven at 325°F until hot all the way through.

This casserole also freezes well. I wrap portions tightly and store them in freezer-safe containers for up to 2 months. To reheat, I let it thaw overnight in the fridge, then bake at 350°F until hot.

FAQs

Do I need to cook the broccoli before adding it to the casserole?

Yes, I always blanch the broccoli for a couple of minutes before mixing it in. It helps keep the texture just right and prevents it from turning mushy in the oven.

Why is my casserole watery after baking?

In my experience, not draining the spinach thoroughly is the most common cause. I always squeeze it out in a clean towel until it’s as dry as possible. Also, make sure the broccoli isn’t overcooked when added.

Can I use rotisserie chicken for this recipe?

Absolutely! I often use rotisserie chicken when I need a shortcut. I just remove the skin, shred the meat, and use about 4 cups for the recipe.

Can I make this casserole ahead of time?

Yes, this is one of those recipes that’s perfect for prepping ahead. I assemble the whole dish, cover it, and refrigerate. Then I just bake it when I’m ready – sometimes adding an extra 5 minutes to the cooking time.

Can I freeze this casserole?

I’ve frozen both whole casseroles and individual portions with success. I recommend letting it cool completely first, then wrapping tightly and storing for up to 2 months. Reheat from thawed for the best texture.

Conclusion

This easy low carb chicken casserole is one of those dependable meals I turn to again and again. It’s hearty, flexible, and ideal for busy weeknights. With just a few staple ingredients and a short prep time, it delivers all the comfort of a classic casserole—without the carbs.