Save My neighbor Sarah showed up one Wednesday evening with a Tupperware container and a knowing smile—she'd made this creamy chicken and broccoli casserole while staying keto and somehow made it look effortless. I was skeptical that anything cheesy and indulgent could fit her strict carb limits, but one forkful changed my mind. The sauce clung to every piece of chicken like silk, and the broccoli had softened into something almost luxurious rather than just virtuous. I pestered her for the recipe that night, and now it's become my go-to when I need comfort food that doesn't derail my goals.
I made this for my book club last month, worried it might feel too heavy or keto-focused for people who weren't dieting. Instead, everyone went quiet for that first bite, and then someone asked for seconds before anyone had even finished their salad. One guest mentioned it reminded her of the casseroles her mom used to make, except better because she didn't feel guilty afterward. That moment stuck with me—this dish has a way of feeling nostalgic and modern at the same time.
Ingredients
- Boneless, skinless chicken breast or thighs (500 g): Thighs stay juicier and more forgiving than breast meat, but either works if you don't overcook it; I usually poach mine gently in broth rather than boiling to keep it tender.
- Broccoli florets (300 g): Steam them just until they're fork-tender but still bright green, not mushy, so they hold their shape in the oven.
- Onion and garlic: The aromatics that wake up the whole dish; don't skip sautéing them first, as raw onion can taste sharp and compete with the cream.
- Heavy cream (120 ml): This is the backbone of your sauce, so use real cream, not half-and-half, or the texture won't be as silky.
- Cheddar and mozzarella cheeses (120 g and 60 g): Cheddar brings flavor, mozzarella brings stretch and melt; together they create that golden, bubbly top everyone fights over.
- Cream cheese (60 g): The secret ingredient that makes the sauce smooth and prevents it from breaking or getting grainy when it bakes.
- Olive oil, paprika, thyme, salt, and pepper: These seasonings are restrained on purpose so the cheese and cream stay the stars, but paprika adds a subtle warmth that ties everything together.
Instructions
- Heat your oven and begin your aromatics:
- Preheat to 190°C (375°F), then warm the olive oil in a skillet over medium heat. Chop your onion finely and sauté it until the edges turn translucent and it starts to smell sweet, about 3 minutes; this is when you know the raw bite is gone.
- Wake up the garlic:
- Add your minced garlic and let it sizzle for just 1 minute—any longer and it can turn bitter. You'll smell when it's right: warm, fragrant, almost nutty.
- Combine everything in a large bowl:
- Layer your casserole:
- Pour the creamy mixture into your prepared casserole dish and spread it so it settles evenly. The mixture should look loose and saucy at this point, which is exactly right.
- Top with the remaining cheese:
- Sprinkle the rest of your cheddar and mozzarella over the top in an even layer; this is what turns golden and creates those crispy, melted edges everyone loves.
- Bake until bubbly and golden:
- Slide it into the oven for 25 to 30 minutes, checking around the 25-minute mark. You'll see bubbles starting around the edges and the cheese turning a deep golden brown—that's your signal it's done.
- Rest before serving:
- Let the casserole sit for 5 minutes after you pull it from the oven; this lets the sauce set just enough so it won't run all over the plate, but it'll still be creamy and warm.
Save 
Save The first time I brought this to a potluck, I was nervous because I'd been doing keto quietly and nobody really knew. When someone asked what was in it and I mentioned the heavy cream and three cheeses, they laughed and said it should not be allowed if you're trying to lose weight. I realized then that this casserole had become my answer to a question I'd been asking myself for months: comfort and goals don't have to be enemies.
Why the Sauce Stays Smooth
The cream cheese in this recipe is not just an ingredient—it's insurance. Traditional cream sauces can break or separate when they bake if the heat is too high or if you don't have enough fat to bind everything together. The cream cheese acts like a buffer, keeping the sauce emulsified and smooth no matter what happens in the oven. I learned this the hard way after making a similar casserole without it and ending up with a grainy, separated sauce that looked sad and tasted worse. Now I make sure the cream cheese is soft before I mix, because cold cream cheese doesn't blend smoothly and leaves little lumps throughout.
Making It Your Own
This recipe is begging to be customized based on what you have and what you love. I've made it with cauliflower instead of broccoli on nights when I had cauliflower rice in the freezer, and it was equally delicious. Some people add cooked bacon or crispy pancetta to the filling, which sounds decadent and honestly works perfectly. A friend of mine stirs in some fresh spinach at the end, and it wilts into the creamy sauce like it was meant to be there all along.
Storing and Reheating Tips
Leftovers keep beautifully for up to three days in the fridge, and I've found that reheating in a low oven (around 160°C) brings the sauce back to life better than the microwave, which can make it grainy. If you're meal-prepping, you can assemble the whole casserole the night before and bake it the next evening, which is a gift when you're busy. The cold cheese will take a few minutes longer to melt and bake, so check it around 30 to 35 minutes instead of 25 to 30.
- Reheat gently and low rather than hot and fast to keep the sauce creamy.
- If the top gets too brown before the inside is heated through, cover it loosely with foil halfway through reheating.
- Pair leftovers with a bright green salad to balance the richness and make a complete meal.
Save 
Save This casserole has become my proof that eating well and eating happily don't have to mean choosing one or the other. It sits on the table golden and steaming, and nobody asks if it's keto or low-carb or diet food—they just eat it and ask for the recipe.
Recipe FAQs
- → Can I use frozen broccoli instead of fresh?
Yes, frozen broccoli works well. Thaw and drain thoroughly before adding to prevent excess moisture in the finished dish.
- → What other vegetables can I substitute?
Cauliflower makes an excellent low-carb alternative. Spinach, zucchini, or green beans also pair nicely with the creamy sauce.
- → Can I prepare this ahead of time?
Assemble the casserole up to 24 hours in advance, refrigerate covered, then bake when ready. Add 5-10 minutes to the baking time if baking cold from the refrigerator.
- → How do I store and reheat leftovers?
Keep refrigerated in an airtight container for up to 3 days. Reheat individual portions in the microwave for 2-3 minutes or warm the entire dish at 160°C (325°F) until heated through.
- → Can I freeze this casserole?
Freeze unbaked or baked portions for up to 3 months. Thaw overnight in the refrigerator before reheating. The texture remains excellent after freezing.
- → What sides pair well with this dish?
A crisp green salad with vinaigrette cuts through the richness. Roasted vegetables like asparagus or Brussels sprouts also complement the creamy flavors nicely.