The ingredients for this recipe are surprisingly simple but they just work (see full printable ingredient list below):

Chicken breast (or chicken tenders)
Chicken broth
Half and half*
All-purpose flour (or use a GF substitute)
Mushrooms
Onion – it disappears into the sauce
Garlic – don’t skip it
Lemon juice – fresh is best

1. Sautee Chicken: Season chicken with salt and pepper and dredge in flour. Heat 3 Tbsp oil in a large skillet over medium/high heat. Once the oil is hot, add chicken and saute until golden, and transfer to a 13×9 casserole baking dish.

How to Make Chicken Casserole step by step with dredging and sautéing chicken

Pro Tip: Work in batches if needed so you don’t crowd your pan. Don’t worry about cooking the chicken through; it still needs to go in the oven

2. Sautee Mushrooms: Add 3 Tbsp oil along and saute mushrooms and onions until soft and golden. Add garlic and saute another 1-2 min. Spread mixture over the chicken.

Sautéing mushrooms, onions and garlic for chicken casserole
3. Make the Sauce: In a medium saucepan (or in the same pan you’ve been using), melt 3 Tbsp butter. Whisk in 3 Tbsp flour until lightly golden (1-2 min). Add 1 1/2 cups chicken broth, 1 Tbsp lemon juice, 1/4 tsp pepper, and whisk until smooth. Add 1 cup half & half and bring to a simmer. Season with salt and pepper to taste.

how to make cream sauce for chicken casserole

4. Combine and Bake: Pour sauce over the chicken casserole. Cover with foil and bake chicken and mushroom casserole at 350˚F for 45 minutes. Garnish with parsley if desired.

Creamy chicken bake in casserole with mushrooms garnished with parsley and served in casserole dish
Serve with
This chicken bakes in gravy so it is great served over Creamy Mashed Potatoes or Egg noodles (the same way we serve Beef Stroganoff). It’s also great paired with these fresh sides:

Baked Asparagus
Cucumber Tomato Salad
Caesar Salad
Roasted Brussels Sprouts
Common Questions
Can I substitute the chicken breast?
You can use trimmed chicken thighs or chicken tenders instead. If using chicken tenders, you don’t need to slice them.

Can I Make this ahead?
Make and combine the chicken and mushrooms and refrigerate. The next day, make the sauce, assemble, and bake as directed.

Does chicken casserole reheat well?
Yes, you can reheat a pre-baked and chilled chicken casserole in the oven: cover with foil and bake at 325˚f for about 20 minutes or just until hot, or reheat on the stovetop over low heat just until hot, stirring occasionally.