A simple one-dish meal, this keto chicken casserole is easy to assemble and practically bakes itself.
Ready in about 40 minutes, it's the ultimate weeknight dinner. And if you happen to have any leftovers, they're great too!
I love casseroles because they make my life so easy. You throw a few ingredients into a baking dish, bake, and voila - dinner is ready! Plus they are tasty, and everyone loves them, kids and adults.
This delicious casserole is keto, filling, and so easy to make. If you have precooked chicken (such as this broiled chicken breast), it's ready in just a few minutes! But even if you need to cook the chicken first, this recipe is still very easy to make.
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Ingredients
Here's an overview of the ingredients you'll need for making this keto chicken casserole. The exact measurements are included in the recipe card below.
Chicken breasts: You can also use rotisserie chicken, but be sure to remove the skin. It will feel rubbery in a casserole.
Kosher salt and black pepper: If using fine salt, you might want to reduce the amount you use.
For the sauce: Mayonnaise (I prefer mayo made with avocado oil), sour cream, Dijon mustard, garlic, spices, and shredded cheddar.
Topping: I like to use scallions and bacon bits.
Instructions
This tasty chicken casserole is the ultimate keto weeknight dinner - easy, quick, and filling. It also has the added advantage of turning boring chicken breasts into something a bit more exciting.
Scroll down to the recipe card for detailed directions. Here are the basic steps for making this recipe:
Cook the chicken. You bake the chicken, then cube it.
Mix the chicken cubes with a creamy homemade sauce.
Transfer the mixture to a baking dish and top it with shredded cheese.
Bake the casserole until hot and bubbly.
Finish the dish: Sprinkle scallions and bacon bits on top for extra flavor and a gorgeous presentation.
Expert tip
This casserole is just creamy enough for my taste, and my family likes it this way too. But if you'd like it to be extra creamy, I suggest you increase the mayonnaise and sour cream to â…“ cup each.
Frequently asked questions
You could if the casserole will be baked for long enough that the chicken is cooked through. But to be on the safe side, I prefer to precook the chicken, then add it to the casserole.
In addition, the raw chicken will release liquids as it cooks, making the dish watery.
Absolutely. Although starch is one of the components of a classic casserole, I make low-carb casseroles all the time without any starch, and they come out wonderfully flavorful.
Yes. You can use boneless skinless chicken thighs in this recipe. Make sure to trim the fat - its texture won't work in a casserole.
Sure. Simply omit the mayonnaise and double the amount of sour cream. It won't be as good - mayonnaise adds extra creaminess and flavor. But it will still be very good.
Variation
If you'd like, you can very lightly steam small broccoli florets and mix them into the casserole before the final stage of baking, making it a complete meal. If you do, I suggest you increase the mayonnaise and sour cream to â…“ cup each.
Serving suggestions
I usually serve this casserole with a green vegetable, such as steamed broccoli or spicy green beans, to round out the meal.
Storing leftovers
You can keep the leftovers in the fridge, in a sealed container, for about 3 days. Gently reheat them, covered, in the microwave on 50% power, to avoid drying out the chicken.
However, if you've used precooked chicken in this recipe that has already spent a couple of days in the fridge, you should take that into account when deciding how long you can keep the leftovers.
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Recipe Card
Cheesy Keto Chicken Casserole
Ingredients
Chicken:
- 4 (8 oz) boneless skinless chicken breasts
- Avocado oil spray
- ½ teaspoon Diamond Crystal kosher salt
- ¼ teaspoon black pepper
Sauce:
- ¼ cup avocado oil mayonnaise (⅓ cup for a creamier casserole)
- ¼ cup sour cream (⅓ cup for a creamier casserole)
- 1 tablespoon Dijon mustard
- 1 tablespoon minced fresh garlic
- ½ teaspoon Diamond Crystal kosher salt
- ¼ teaspoon black pepper
- ½ teaspoon dried thyme
- ½ teaspoon paprika
- ¼ teaspoon cayenne pepper
- 1 cup shredded sharp cheddar, divided
Topping:
- ¼ cup sliced scallions (green parts)
- ¼ cup bacon bits room temperature
Instructions
- Preheat your oven to 450 degrees F. Line a baking dish with foil and grease the foil. Arrange the chicken breasts in the prepared pan. Spray them with oil and sprinkle with salt and pepper. Bake until cooked through, about 20 minutes.
- Meanwhile, grease a 2-quart casserole dish. In a large bowl, mix together the mayonnaise, sour cream, Dijon mustard, minced garlic, salt, pepper, dried thyme, paprika, cayenne, and ½ cup of the shredded cheddar.
- When the chicken is cooked, remove it from the oven but keep the oven on. Allow the chicken to slightly cool, until it’s easier to handle. Cut it into cubes or shred it. Add the chicken cubes to the bowl with the mayonnaise-sour cream mixture and toss to coat.
- Transfer the mixture to the prepared casserole dish. Sprinkle with the remaining ½ cup of shredded cheddar. Bake until the cheese is melted, 5-10 minutes. If your casserole dish is broiler-safe, you can broil it instead, 6 inches below the broiler element (not directly below), for 30 seconds to 1 minute.
- Sprinkle the casserole with sliced scallions and bacon bits. Serve immediately.
Video
Notes
Add Your Own Notes
Nutrition per Serving
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Vered DeLeeuw, LL.M., CNC, has been following a low-carb real-food diet and blogging about it since 2011. She's a Certified Nutrition Coach (NASM-CNC), has taken courses at the Harvard School of Public Health, and has earned a Nutrition and Healthy Living Certificate from Cornell University. Her work has appeared in several major media outlets, including Healthline, HuffPost, Today, Women's Health, Shape, and Country Living. 
Kylie
This was yummy. I made the avocado keto mayo - this was easy. I also baked the chicken breast. I added red bell pepper and 1/2 an onion to the casserole. I will make this again. Thanks!
Vered DeLeeuw
You're very welcome, Kylie! I like your additions.
Esme
This casserole is not only easy, but utterly delicious! Vered, the seasoning is perfect, and everyone in the family loved it! I did add steamed broccoli to make it a complete meal, just as you described in the Notes. I'll try some spinach next time to introduce another green veggie. I did cheat because I was short on time, so I used a rotisserie chicken instead of baking chicken breasts. I can't wait to make this again, it's so good! Thank you for this elevated chicken casserole recipe!
Vered DeLeeuw
I'm so glad you enjoyed this casserole, Esme! I love using rotisserie chicken in recipes. It makes life so much easier.
Renee
Absolutely delicious! I baked chicken thighs for about 45 minutes instead of chicken breast. I also added steamed broccoli, cauliflower, zucchini, and carrot. The kids and husband loved it too!
Vered DeLeeuw
How wonderful that the entire family enjoyed this casserole, Renee! I love your additions.