This simple creamy chicken casserole is the ultimate low carb dinner idea for busy nights. Juicy chicken, velvety cream cheese sauce, and fresh veggies come together in under 30 minutes…

Ingredients

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Instructions

Step 1

Preheat your oven to 375°F (190°C). While the oven is heating, gather all your ingredients. This step ensures a smooth cooking process and prevents any last-minute scrambling. If you haven’t already cooked your chicken, you can quickly poach it: place the chicken breasts in a pot, cover with water or broth, bring to a gentle boil, then reduce heat and simmer for 12-15 minutes until the internal temperature reaches 165°F (74°C). Let it cool slightly, then shred using two forks or a hand mixer on low speed. Alternatively, use leftover rotisserie chicken for an even faster prep. The shredded chicken should be in bite-sized pieces, not too fine, to maintain texture in the casserole.

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Step 2

In a large skillet or sauté pan, heat 2 tablespoons of olive oil over medium heat. Add the diced onion and cook for 3-4 minutes until translucent and fragrant, stirring occasionally. The onion should soften but not brown; if it starts to brown, reduce the heat slightly. Add the minced garlic and cook for another 30 seconds until aromatic. Garlic burns quickly, so keep it moving. The combination of onion and garlic forms the flavor base of the sauce, providing sweetness and depth without any carbs. If you’re using frozen broccoli, add it now and cook for 2-3 minutes to remove excess moisture, which helps prevent a watery casserole.

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Step 3

Reduce the heat to low and add the softened cream cheese to the skillet. Stir continuously until the cream cheese is fully melted and incorporated with the onion mixture. This should take about 2 minutes. The cream cheese creates a velvety, rich base that is the hallmark of this low carb comfort dish. Make sure the cream cheese is at room temperature before adding; cold cream cheese will clump and result in a lumpy sauce. If you see any lumps, whisk vigorously until smooth.

Step 4

Slowly pour in the chicken broth and heavy cream, whisking constantly to combine. Increase the heat to medium and bring the sauce to a gentle simmer, then reduce heat to low. Let it cook for 3-4 minutes, stirring occasionally, until the sauce thickens slightly. The sauce should coat the back of a spoon; if it’s too thin, let it simmer a bit longer. Season with dried thyme, garlic powder, salt, and black pepper. Taste and adjust seasoning – the Parmesan will add saltiness later, so go easy on the salt. The sauce should be creamy, savory, and aromatic with thyme.

Step 5

Add the shredded chicken and broccoli florets to the skillet, stirring gently to coat everything evenly with the sauce. Cook for 2 minutes to warm the chicken and broccoli through. The mixture should be thick and clingy, not soupy. If it seems too thick, add a splash more chicken broth. Transfer the entire mixture to a greased 9×13-inch (or similar) baking dish, spreading it into an even layer. Sprinkle the shredded mozzarella and grated Parmesan evenly over the top. The cheeses will melt into a golden, bubbly crust.

Step 6

Place the baking dish in the preheated oven and bake for 15-20 minutes, until the casserole is hot and bubbly and the cheese on top is melted and lightly golden. For a browner top, switch to broil for the last 2-3 minutes, watching carefully to avoid burning. Remove from the oven and let it rest for 5 minutes before serving. This resting time allows the casserole to set and makes serving easier. Garnish with chopped fresh parsley for a pop of color and freshness. Serve warm and enjoy the creamy, comforting goodness without the carbs!

For best results

  • For the best texture, use freshly shredded mozzarella from a block rather than pre-shredded cheese. Pre-shredded cheese often contains anti-caking agents like potato starch or cellulose, which can prevent smooth melting and may add unwanted carbs. Grating your own cheese ensures a silky, stretchy melt that beautifully blankets the casserole. It takes just a few extra minutes but makes a noticeable difference in the final dish.
  • If you prefer a dairy-free version, you can substitute the cream cheese with a dairy-free cream cheese alternative, use full-fat coconut cream instead of heavy cream, and choose a dairy-free mozzarella shred. Keep in mind that the flavor and texture will vary; coconut cream adds a slight sweetness that pairs well with the savory elements. Also, reduce the baking time slightly as dairy-free cheeses can become rubbery if overbaked.
  • To make this casserole even more budget-friendly, use chicken thighs instead of breasts. Thighs are generally more affordable and stay juicier during cooking due to their higher fat content. You can also bulk up the casserole with additional low-carb vegetables like cauliflower florets, sliced zucchini, or bell peppers. Just be mindful of the water content; sauté zucchini briefly to remove excess moisture before adding.
  • This casserole is perfect for meal prep. Assemble the casserole completely but do not bake it. Cover tightly with foil and refrigerate for up to 2 days. When ready to bake, remove from the fridge while the oven preheats, then bake as directed, adding 5-10 minutes to the cooking time since it starts cold. You can also freeze the unbaked casserole for up to 3 months; thaw overnight in the fridge before baking.
  • If you want a crispier top, mix 1/4 cup of crushed pork rinds with 2 tablespoons of melted butter and sprinkle over the cheese before baking. This creates a crunchy, keto-friendly topping that mimics breadcrumbs. Alternatively, use almond flour mixed with Parmesan for a nutty crust. Either option adds texture without the carbs.
  • To ensure your sauce is perfectly smooth, always soften the cream cheese to room temperature before adding it to the skillet. Cold cream cheese will seize up and create lumps that are difficult to smooth out. If you forget to take it out ahead of time, cut it into small cubes and microwave on low power in 10-second bursts until softened but not melted.

Variations

  • **Keto Bacon Ranch Casserole**: Add 6 slices of cooked, crumbled bacon and replace the thyme with 1 tablespoon of ranch seasoning mix (make sure it's sugar-free). The smoky, tangy flavor of ranch pairs beautifully with the creamy sauce and chicken. Top with extra bacon and fresh chives before serving. This variation is a surefire hit with ranch lovers and adds a satisfying crunch.
  • **Spicy Buffalo Chicken Casserole**: Stir 1/4 cup of buffalo sauce (or to taste) into the cream sauce along with an extra 2 tablespoons of melted butter. Use blue cheese crumbles instead of Parmesan and drizzle additional buffalo sauce over the top before baking. Serve with celery sticks and a side of ranch or blue cheese dressing for dipping. This version brings heat and tang, perfect for game day or spice enthusiasts.
  • **Mediterranean Chicken Casserole**: Replace broccoli with 1 cup of chopped artichoke hearts (canned or frozen, drained) and 1/2 cup of sun-dried tomatoes (rehydrated and chopped). Use feta cheese instead of mozzarella and add a teaspoon of dried oregano. Garnish with fresh basil and a squeeze of lemon juice. This variation offers a bright, tangy flavor profile reminiscent of Greek cuisine.
  • **Vegetarian Option**: Omit the chicken and double the broccoli or substitute with cauliflower, mushrooms, and spinach. Add a can of drained and rinsed chickpeas for extra protein (though this increases carbs slightly). Use vegetable broth instead of chicken broth. The cream sauce is hearty enough to stand on its own, and the vegetables provide a satisfying texture.
  • **Cajun Chicken Casserole**: Season the chicken with Cajun seasoning (homemade or store-bought) before cooking. Add 1/2 cup of diced bell peppers and 1/2 cup of sliced andouille sausage (optional) to the skillet with the onion. Replace thyme with 1 teaspoon of smoked paprika and a pinch of cayenne. Top with pepper jack cheese for a spicy, smoky kick that evokes Louisiana flavors.

Nutrition

  • Calories385 kcal
  • Total Fat28g
  • Saturated Fat14g
  • Cholesterol115mg
  • Sodium620mg
  • Total Carbohydrates9g
  • Dietary Fiber2g
  • Sugars4g
  • Protein28g

Common Questions

Can I use raw chicken instead of pre-cooked chicken?
Yes, but you’ll need to adjust the cooking time. If using raw chicken, cut it into bite-sized pieces and cook it in the skillet with the onions until no longer pink (about 6-8 minutes). Then proceed with the recipe as written. However, pre-cooked or rotisserie chicken is recommended for convenience and to ensure the chicken doesn’t become dry during baking. If you do use raw chicken, make sure it reaches an internal temperature of 165°F (74°C) before serving.
How do I store leftovers and how long do they last?
Store any leftover casserole in an airtight container in the refrigerator for up to 4 days. To reheat, place individual portions in the microwave for 1-2 minutes or reheat in a 350°F (175°C) oven for 10-15 minutes until warmed through. You can also freeze the casserole for up to 3 months. Thaw overnight in the fridge before reheating. The texture may be slightly softer after freezing due to the cream sauce, but it will still be delicious.
Can I make this casserole ahead of time?
Absolutely! This casserole is ideal for make-ahead meals. Assemble the casserole completely (do not bake), cover tightly with foil or plastic wrap, and refrigerate for up to 2 days. When ready to serve, remove from the fridge while the oven preheats, then bake as directed, adding 5-10 minutes to the cooking time since it starts cold. You can also freeze the unbaked casserole; just thaw overnight in the refrigerator before baking.
Is this recipe gluten-free?
Yes, this recipe is naturally gluten-free as it contains no flour, pasta, or other gluten-containing ingredients. However, always check labels on chicken broth, cream cheese, and seasonings to ensure they are certified gluten-free, as some brands may contain additives or be processed in facilities that handle gluten. The casserole is also low carb and keto-friendly, with approximately 7g net carbs per serving.
Can I substitute the heavy cream with something lighter?
For a lower-fat option, you can use half-and-half or whole milk, but the sauce will be thinner and less creamy. To compensate, you can thicken the sauce with a slurry of 1 tablespoon of xanthan gum mixed with 2 tablespoons of water (whisked in at the end) or use an extra ounce of cream cheese. Keep in mind that using milk will increase the carb content slightly. For a dairy-free alternative, unsweetened canned coconut milk (full fat) works well and keeps the sauce rich.
Why is my casserole watery?
A watery casserole is usually caused by excess moisture from vegetables or not cooking the sauce long enough to thicken. To prevent this, make sure to thaw frozen broccoli completely and pat it dry with paper towels before adding. If using fresh broccoli, blanch it briefly and drain well. Also, ensure the sauce simmers until it coats the back of a spoon before adding the chicken and broccoli. If the casserole is already baked and watery, you can drain off excess liquid or return it to the oven uncovered for an additional 5-10 minutes to evaporate moisture.
Can I add other vegetables or protein?
Certainly! This casserole is very versatile. You can add cauliflower florets, sliced mushrooms, chopped bell peppers, or spinach (add spinach at the end and stir until wilted). For protein, try cooked Italian sausage, diced ham, or shrimp. If using shrimp, add them during the last 5 minutes of baking to avoid overcooking. Just be mindful of the carb content of added vegetables and adjust your serving size accordingly.