If your meal prep always starts strong and then turns into sad, soggy leftovers by Wednesday… this one’s for you. This low carb chicken casserole was built specifically to reheat like a champ: creamy, cozy, and still tasty after a few trips through the microwave.
It’s packed with protein, sneaks in veggies, and skips the heavy carb fillers without feeling “diet food.” Make it once, portion it out, and enjoy actually-good lunches all week.
Why You’ll Love This
This casserole is rich and satisfying without pasta or rice, holds its texture after reheating, and portions easily for grab-and-go meal prep—aka the weeknight/lunchbox win you’ve been wanting.
Ingredients
- 2 lbs boneless, skinless chicken breast (or thighs), cut into bite-size pieces
- 1 tbsp olive oil
- 1 tsp kosher salt (plus more to taste)
- 1/2 tsp black pepper
- 1 tsp garlic powder
- 1 tsp onion powder
- 1 tsp smoked paprika
- 4 cups broccoli florets, chopped small (fresh or frozen)
- 8 oz cauliflower rice (about 2 1/2 cups), fresh or frozen
- 4 oz cream cheese, softened
- 1/2 cup sour cream (or plain Greek yogurt)
- 3/4 cup chicken broth
- 2 cups shredded cheddar cheese, divided
- 1/2 cup grated parmesan cheese
- 1 tbsp Dijon mustard (optional but highly recommended)
- 2 tbsp chopped green onions (optional, for finishing)
How to Make It
- Preheat your oven to 375°F. Lightly grease a 9×13-inch casserole dish (or two smaller dishes for easier meal prep).
- Season the chicken with salt, pepper, garlic powder, onion powder, and smoked paprika.
- Heat olive oil in a large skillet over medium-high heat. Sear the chicken for 4–6 minutes, stirring occasionally, until lightly browned (it doesn’t need to be fully cooked yet).
- If using frozen broccoli or frozen cauliflower rice, quickly microwave or sauté just until no longer icy, then drain off any excess liquid. This is the secret to non-watery leftovers.
- In a large bowl, whisk together cream cheese, sour cream, chicken broth, 1 1/2 cups cheddar, parmesan, and Dijon (if using) until smooth and creamy.
- Add chicken, broccoli, and cauliflower rice to the bowl. Stir until everything is evenly coated in the sauce.
- Spread the mixture into the prepared casserole dish. Top with the remaining 1/2 cup cheddar cheese.
- Bake for 20–25 minutes, until bubbly around the edges and the chicken is cooked through (165°F in the center).
- Cool for 10–15 minutes before slicing and portioning. Finish with green onions if you want it to feel extra “fresh meal” instead of “meal prep.”
Tips for the Best Results
- Dry your veggies. Frozen broccoli and cauliflower rice hold a ton of water. Thaw and drain (or squeeze in a clean towel) so your casserole stays creamy, not soupy.
- Don’t overbake. Overcooked chicken gets dry when reheated. Bake just until done and bubbling.
- Cut everything small. Smaller broccoli pieces reheat more evenly and make each bite balanced (aka not “all broccoli” or “all chicken”).
- Use full-fat dairy for best texture. Low-fat cream cheese can split and get grainy after reheating.
- Let it cool before sealing. Trapping steam in containers can add moisture and make it watery by day two.
Variations
- Buffalo chicken: Add 1/3 cup buffalo sauce and swap cheddar for mozzarella. Top with crumbled blue cheese if that’s your vibe.
- Mexi-style: Add 1 tsp cumin, 1/2 tsp chili powder, and 1/2 cup salsa (thick, not watery). Use pepper jack cheese.
- Extra veggie: Stir in 1 cup chopped spinach (fresh) or sautéed mushrooms for more volume without extra carbs.
- Rotisserie shortcut: Use 4 cups shredded rotisserie chicken and skip the searing step—just mix and bake until hot and bubbly.
- Crunchy topping (still low carb): Mix 1/2 cup crushed pork rinds with 2 tbsp melted butter and sprinkle on top before baking.
Storage & Reheating
Store portions in airtight containers in the fridge for up to 4 days. Reheat in the microwave at 70–80% power in 60–90 second bursts, stirring once if your container allows, until hot throughout. For best texture, add a tiny splash of broth before reheating if it looks thick, or reheat covered in a 350°F oven for about 10–15 minutes.
FAQ
How many meal prep portions does this make?
You’ll get about 6 portions if you’re using it as a main dish (roughly 1 1/2 cups each). If you pair it with a side salad or extra veggies, you can stretch it to 7–8 smaller portions.
Why does my casserole get watery after reheating?
Almost always it’s from extra moisture in the broccoli or cauliflower rice. Thaw frozen veggies, drain well, and squeeze out excess liquid if needed. Also cool the casserole before sealing containers so steam doesn’t turn into water droplets inside.
Can I freeze this low carb chicken casserole?
Yes. For best results, freeze individual portions in freezer-safe containers for up to 2 months. Thaw overnight in the fridge, then reheat gently (microwave at 70–80% power or in a covered dish in the oven). The texture stays creamy, but a little extra stirring helps bring the sauce back together.
What’s the best container for meal prep so it reheats evenly?
Shallow, single-serving containers work best because the casserole heats through without overcooking the edges. Glass containers are great for even heat, but any microwave-safe container is fine—just don’t pack portions too thick.
Can I make it ahead and bake it later?
Totally. Assemble everything, cover tightly, and refrigerate up to 24 hours. When you’re ready, bake at 375°F until hot and bubbly (usually 25–35 minutes since it’s starting cold). If the top browns too fast, loosely cover with foil.