Creamy Chicken & Potato Casserole with Onion–Mushroom Sauté and Fresh Side Salad

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This Creamy Chicken & Potato Casserole with Onion–Mushroom Sauté and Fresh Side Salad is a comforting one-dish meal that balances hearty layers of tender potatoes, marinated chicken, and umami-rich onions and mushrooms beneath a luscious cheese-mayo topping. Finished with fresh tomato slices and served alongside a crisp lettuce–cucumber salad, it’s a symphony of textures and flavors—from creamy and savory to bright and refreshing. Perfect for family dinners, potlucks, or meal prep, this casserole requires simple ingredients and delivers maximum satisfaction.

Cooking Time

Preparation: 20 minutes

First Bake (covered): 35 minutes
Topping Prep & Final Bake: 15 minutes
Salad Assembly: 10 minutes (overlapping)

Resting: 10 minutes
Total Active Time: 50 minutes
Total Time: Approximately 1 hour 35 minutes

Ingredients

For the Casserole

5–6 medium potatoes (≈800 g), peeled and thinly sliced

2 chicken breasts (≈400 g), sliced or cubed
1 Tbsp olive oil (for chicken marinade)
½ tsp salt

¼ tsp sweet paprika

For the Vegetable Sauté

2 onions, finely chopped
2 Tbsp olive oil
½ tsp salt

¼ tsp ground black pepper
1 tsp Italian seasoning
2 garlic cloves, minced

150 g mushrooms, sliced

For the Creamy Topping

100 g grated cheese (mozzarella, Gouda, or cheddar)
2 tomatoes, sliced
1 large egg

⅓ cup (80 ml) mayonnaise
1 Tbsp chopped fresh parsley

For the Side Salad

Fresh lettuce leaves (≈100 g), torn
1 tomato, diced

½ cucumber, sliced
1 Tbsp chopped fresh parsley
½ tsp salt

¼ tsp sweet paprika
1 Tbsp olive oil

Step-by-Step Cooking Directions

Marinate the Chicken
In a bowl, combine chicken pieces with 1 Tbsp olive oil, ½ tsp salt, and ¼ tsp sweet paprika. Toss thoroughly and set aside to marinate while you prep the potatoes and vegetables.

Prep & Layer Potatoes
Preheat oven to 180 °C (360 °F). Grease a large baking dish. Drain potato slices from their water bath and pat dry. Layer half the potato slices evenly on the bottom of the dish.
Sauté Onions & Mushrooms
Heat 2 Tbsp olive oil in a skillet over medium heat. Sauté onions for 3–4 minutes until translucent. Season with ½ tsp salt, ¼ tsp pepper, and 1 tsp Italian seasoning. Stir in garlic and mushrooms; cook until mushrooms release liquid and turn golden, about 5 minutes. Remove from heat.
Assemble Casserole Base
Arrange marinated chicken over the potato layer. Spread the onion–mushroom sauté evenly atop the chicken. Top with remaining potato slices.

First Bake (Covered)
Cover with foil and bake 35 minutes. Potatoes should be almost tender and chicken mostly cooked.
Prepare Creamy Topping
In a bowl, whisk egg, mayonnaise, and chopped parsley until smooth. Stir in grated cheese.
Add Tomatoes & Topping
Remove casserole from oven and discard foil. Arrange tomato slices over the potatoes. Pour creamy cheese mixture over tomatoes, spreading to cover.

Final Bake (Uncovered)
Return to oven and bake 15 minutes until topping is golden and bubbly. Let rest 10 minutes before serving.
Assemble Side Salad
Toss lettuce, diced tomato, cucumber, and parsley with salt, paprika, and olive oil. Chill until ready to serve.
Serve
Cut casserole into squares, plate alongside a portion of fresh salad, and enjoy warm.

Nutritional Information (per serving; serves 6)

Calories: 460 kcal
Protein: 28 g
Carbohydrates: 36 g
- Fiber: 5 g
- Sugars: 6 g
Fat: 22 g
- Saturated Fat: 8 g
Sodium: 780 mg

The Origins and Popularity of the Recipe

Layered potato and meat bakes are classic comfort foods across many cuisines—French gratin dauphinois, British shepherd’s pie, and Eastern European casseroles share the same heartiness. This variant, which combines sautéed mushrooms and onions, is popular in modern home cooking for its depth of flavor and easy assembly. The mayonnaise-cheese topping nods to American-style bakes, while the side salad adds a fresh contrast, reflecting the current trend toward balanced plates.

Reasons Why You’ll Love the Recipe

One-Dish Simplicity: Minimal cleanup; bake covers starch, protein, and veg.
Layered Flavors: Smoky paprika, aromatic Italian herbs, umami mushrooms, and creamy cheese.

Textural Contrast: Tender potatoes, juicy chicken, and crisp-tender salad.
Family-Friendly: Mild seasoning appeals to kids and adults alike.
Make-Ahead Flexibility: Pre-assemble and refrigerate before baking.

Health Benefits

Potatoes: Provide vitamin C, potassium, and fiber for digestive health.
Chicken: Supplies lean protein for muscle maintenance.
Onions & Garlic: Contain antioxidants and compounds that support immune function.

Mushrooms: Offer B-vitamins and minerals like selenium.
Fresh Salad: Adds hydration, vitamins, and fiber with minimal calories.

Serving Suggestions

Pair with warm whole-grain bread or dinner rolls.

Offer a side of steamed green beans or broccoli for extra veg.
Serve with a light white wine, such as Pinot Grigio, or iced herbal tea.

Common Mistakes to Avoid

Skipping Potato Pre-bath: Let potatoes sit in water to remove starch and prevent sticking.

Overcrowding Veggies: Sauté mushrooms in batches if needed to avoid steaming.
Under-seasoning Layers: Taste each component and adjust salt and pepper before layering.
Removing Foil Too Early: Keep covered until potatoes are mostly tender to avoid drying out.

Pairing Recommendations

Wine: A crisp Chardonnay or Sauvignon Blanc cuts through the richness.
Beer: A light lager or amber ale complements savory mushrooms and cheese.
Non-Alcoholic: Sparkling water with lemon or cucumber slices refreshes the palate.

Cooking Tips

Uniform Slices: Use a mandolin to slice potatoes evenly for consistent baking.
Creamy Topping: Let the mixture rest briefly for bubbles to settle, ensuring smooth coverage.
Cheese Choice: Feel free to blend mozzarella with sharp cheddar or Gruyère for deeper flavor.

Herb Variation: Swap parsley for chives or tarragon in both topping and salad for a flavor twist.

Similar Recipes to Try

Classic Shepherd’s Pie: Ground meat under mashed potato.
Mushroom & Spinach Gratin: Layers of veg in a cheesy béchamel.
Chicken Pot Pie Casserole: Chicken, veg, and puff pastry topping.

Variations to Try

Spicy Kick: Add ½ tsp chili flakes to the chicken marinade and topping.
Vegetarian Option: Omit chicken; increase mushrooms and add cooked lentils.
Herb Crust: Mix breadcrumbs, Parmesan, and herbs into the topping for crunch.
Dairy-Free: Use dairy-free cheese and omit mayonnaise, substituting blended silken tofu.

Ingredient Spotlight: Mushrooms

Mushrooms contribute earthiness, moisture, and a meaty texture. Rich in umami, B-vitamins, and antioxidants, they enhance flavor complexity while boosting nutritional value. Sautéed until golden, they form a savory bridge between chicken and potatoes.

Conclusion

This Creamy Chicken & Potato Casserole with Onion–Mushroom Sauté and Fresh Side Salad brings comfort, convenience, and nutrition to your table. With layered flavors, contrasting textures, and simple preparation, it’s destined to become a household favorite. Whether you’re seeking a cozy family dinner or a make-ahead dish for entertaining, this recipe delivers satisfaction in every bite.

Frequently Asked Questions

1. Can I use sweet potatoes instead of white potatoes?
Yes—slice sweet potatoes similarly and adjust baking time by 5 minutes if needed.

2. How far ahead can I assemble the casserole?
Assemble, cover, and refrigerate up to 24 hours before baking; add 5 minutes to bake time.

3. What if I don’t have mayonnaise?
Substitute an equal amount of sour cream or Greek yogurt for tangier flavor.

4. Can I freeze leftovers?
Freeze cooled portions in airtight containers for up to 2 months; thaw overnight and reheat in oven.

5. How do I prevent watery topping?
Use full-fat mayonnaise and squeeze excess moisture from tomato slices before layering.

6. My potatoes are undercooked—why?
Ensure they’re sliced thinly and rest in water before baking; consider par-boiling thicker slices 3 minutes.

7. Can I add other vegetables?
Yes—layer in spinach, bell peppers, or zucchini for more variety.

8. How do I make it dairy-free?
Use dairy-free cheese and vegan mayo, or omit topping and serve with a tomato-olive salsa.

9. What cheese works best?
Mozzarella melts smoothly; Gouda or cheddar adds depth. A blend is even better.

10. Why rest the casserole before serving?
Resting lets juices redistribute and topping set, ensuring clean slices and optimal texture.