Chicken and French Onion Casserole

Indulge in the decadence of this Chicken and French Onion Casserole, a comforting fusion of tender, seared chicken breasts and rich, caramelized onions enveloped in a creamy, thyme-infused sauce. Topped with a heavenly layer of Gruyere and mozzarella cheeses, then finished with a golden, crunchy panko breadcrumb topping, this dish captures the essence of French onion soup in casserole form. The recipe combines bold flavors with easy-to-follow steps, making it an ideal centerpiece for weeknight dinners or cozy gatherings. Ready in just over an hour and perfect for serving a crowd, this cheesy, aromatic casserole is a guaranteed crowd-pleaser. Garnish with fresh parsley for an elegant touch and serve it with crusty bread or a side salad to complete the meal.

Nutriscore Rating: 65/100

Prep Time:20 mins

Cook Time:45 mins

Total Time:65 mins

Servings: 6

Ingredients

• 3 pieces Boneless, skinless chicken breasts
• 1 teaspoon Salt
• 1 teaspoon Black pepper
• 2 tablespoons Olive oil
• 2 tablespoons Butter
• 3 pieces Large yellow onions
• 1 teaspoon Fresh thyme leaves
• 2 teaspoons Minced garlic
• 2 tablespoons All-purpose flour
• 1.5 cups Beef broth
• 0.5 cups Heavy cream
• 1 cup Shredded Gruyere cheese
• 0.5 cups Shredded mozzarella cheese
• 0.75 cups Panko breadcrumbs
• 2 tablespoons Chopped fresh parsley (optional, for garnish)

Directions

Step 1

Preheat your oven to 375°F (190°C).

Step 2

Season the chicken breasts with salt and black pepper on both sides.

Step 3

Heat olive oil in a large skillet over medium-high heat. Sear the chicken for 3-4 minutes on each side until golden brown but not fully cooked. Transfer the chicken to a plate and set aside.

Step 4

In the same skillet, melt the butter over medium heat. Add the sliced onions and sprinkle with a pinch of salt. Cook, stirring occasionally, for 15-20 minutes, or until the onions are soft and caramelized.

Step 5

Add the thyme leaves and minced garlic to the onions, cooking for an additional 1-2 minutes until fragrant.

Step 6

Sprinkle the flour over the onion mixture and stir to coat. Gradually add the beef broth while stirring, ensuring there are no lumps. Simmer for 2-3 minutes until the sauce thickens slightly.

Step 7

Lower the heat and stir in the heavy cream. Adjust seasoning with salt and pepper if needed.

Step 8

Return the seared chicken breasts to the skillet, nestling them in the onion mixture. Spoon some of the sauce over the chicken to coat.

Step 9

Transfer the mixture to a lightly greased 9x13-inch casserole dish. Sprinkle the Gruyere and mozzarella cheeses evenly over the top.

Step 10

In a small bowl, mix the panko breadcrumbs with 1 tablespoon of olive oil or melted butter. Sprinkle the breadcrumb mixture evenly over the cheese layer.

Step 11

Bake the casserole, uncovered, for 25-30 minutes, or until the chicken is fully cooked (internal temperature of 165°F/74°C) and the topping is golden brown.

Step 12

Allow the casserole to rest for 5 minutes before serving. Garnish with fresh parsley if desired.

Nutrition Facts

Serving size	(1744.6g)

Amount per serving	% Daily Value*
Calories	2765.4

Total Fat 160.9g	0%
Saturated Fat 73.8g	0%
Polyunsaturated Fat 3.4g
Cholesterol 789.7mg	0%
Sodium 5842.0mg	0%
Total Carbohydrate 88.8g	0%
Dietary Fiber 10.2g	0%
Total Sugars 23.7g
Protein 224.6g	0%

Vitamin D 33.7IU	0%
Calcium 1709.1mg	0%
Iron 10.0mg	0%
Potassium 2392.3mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 53.6%

Protein: 33.3%

Carbs: 13.1%