Favorite Fish Casserole

Creamy, comforting, and irresistibly crispy on top, this Favorite Fish Casserole is the ultimate hearty weeknight dinner dish. Featuring tender, flaky white fish fillets like cod, tilapia, or haddock, the casserole is layered with a velvety cheese sauce infused with Dijon mustard, garlic, and fresh parsley. Its golden breadcrumb topping, moistened with olive oil, adds a delightful crunch to every bite. Ready in under an hour, this recipe combines the richness of a homemade roux with the subtle zest of lemon juice to create a perfectly balanced flavor profile. Serve it with rice, potatoes, or a crisp green salad for a complete, satisfying meal that’s sure to become a household favorite.

Nutriscore Rating: 61/100

Prep Time:20 mins

Cook Time:35 mins

Total Time:55 mins

Servings: 4

Ingredients

• 600 grams white fish fillets (e.g., cod, tilapia, or haddock)
• 1 teaspoon salt
• 0.5 teaspoon black pepper
• 2 tablespoons lemon juice
• 3 tablespoons unsalted butter
• 1 medium yellow onion, finely chopped
• 2 garlic cloves, minced
• 3 tablespoons all-purpose flour
• 375 milliliters milk
• 125 milliliters heavy cream
• 1 teaspoon Dijon mustard
• 150 grams shredded cheese (e.g., cheddar or Gruyère)
• 2 tablespoons fresh parsley, chopped
• 1 cup breadcrumbs
• 2 tablespoons olive oil

Directions

Step 1

Preheat your oven to 190°C (375°F). Grease a 9x13-inch (23x33 cm) baking dish lightly with butter or cooking spray.

Step 2

Pat the fish fillets dry with paper towels. Season both sides with salt, black pepper, and a drizzle of lemon juice. Lay the fillets in the prepared baking dish in a single layer.

Step 3

In a medium saucepan, melt 3 tablespoons of butter over medium heat. Add the chopped onion and cook until softened (about 4-5 minutes). Stir in the minced garlic and cook for another minute until fragrant.

Step 4

Sprinkle the flour over the onion and garlic mixture, stirring constantly, and cook for 1-2 minutes to form a roux.

Step 5

Gradually whisk in the milk and heavy cream, ensuring there are no lumps. Bring the sauce to a gentle simmer, stirring frequently, until it thickens (about 3-4 minutes).

Step 6

Remove the sauce from the heat and stir in the Dijon mustard, shredded cheese, and fresh parsley. Continue stirring until the cheese has fully melted and the sauce is smooth. Taste and adjust seasoning as needed.

Step 7

Pour the cheese sauce evenly over the fish fillets in the baking dish, ensuring they are fully covered.

Step 8

In a small bowl, combine the breadcrumbs with olive oil until the mixture is evenly moistened. Sprinkle the breadcrumb mixture evenly over the top of the sauce.

Step 9

Bake the casserole in the preheated oven for 25-30 minutes, or until the fish is cooked through and flakes easily with a fork, and the topping is golden brown and crispy.

Step 10

Remove the casserole from the oven and let it rest for 5 minutes before serving. Garnish with more chopped parsley if desired. Serve warm with a side of rice, potatoes, or a fresh green salad.

Nutrition Facts

Serving size	1625.3 grams (1625.3g)

Amount per serving	% Daily Value*
Calories	2876

Total Fat 175.30g	225%
Saturated Fat 89.70g	449%
Polyunsaturated Fat 2.90g
Cholesterol 714mg	238%
Sodium 5701mg	248%
Total Carbohydrate 139.50g	51%
Dietary Fiber 7.10g	25%
Total Sugars 32.00g
Protein 190.10g	380%

Vitamin D 1402IU	7011%
Calcium 1799mg	138%
Iron 10mg	53%
Potassium 2844mg	61%

*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: 54.5%

Protein: 26.3%

Carbs: 19.3%