Fish Casserole with Vegetables and Cheese Sauce

Looking for a comforting, flavorful, and easy-to-make meal? This Fish Casserole with Vegetables and Cheese Sauce is your answer! It's a fantastic way to turn simple pollock fillets and a bag of frozen vegetables into a wholesome and satisfying dinner that the whole family will love. The tender, flaky fish, combined with colorful veggies and a rich, creamy cheese sauce, creates a harmonious dish that's baked to golden perfection. It's the ultimate comfort food, perfect for a cozy weeknight dinner or a relaxed weekend meal.

Cooking: 1 hour
Quantity: 6 Servings
Per serving
Calories: 345 kcal
Proteins: 42 g
Fats: 15 g
Carbohydrates: 11 g

Ingredients for the Fish Casserole

  • 1 kg (2.2 lbs) pollock
  • 250 g (8.8 oz) frozen vegetable mix (we used green peas, green beans, carrots, corn kernels, bell pepper)
  • 1 onion
  • 3 eggs
  • 80 g (2.8 oz) cheese
  • 2 tbsp 15% smetana (a type of sour cream)
  • 1 tbsp sunflower oil
  • 1/2 tsp salt
  • 1 tsp Italian herbs

How to Make Fish Casserole with Vegetables and Cheese Sauce

Thaw and rinse the pollock. Cut each fish along the spine to separate the fillets. For our pollock casserole, you don’t need large, whole fillets; separate the flesh from the skin and bones in any convenient way.

Raw pollock fillets being separated from the skin and bones on a cutting board.

Separating the pollock fillet from the skin and bones

Sprinkle the fillets with Italian herbs and salt. Mix the prepared pollock pieces.

Pieces of raw pollock fillet in a bowl being seasoned with salt and Italian herbs.

Sprinkling the fish with Italian herbs and salt

Grease the bottom and sides of a ceramic baking dish with sunflower oil. Slice the onion into rings and line the bottom of the dish.

Sliced raw onions layered at the bottom of a ceramic baking dish.

Placing sliced onion at the bottom of the prepared dish

Sprinkle the frozen vegetables over the onion and drizzle with sunflower oil.

Arrange a layer of pollock fillets, spreading them evenly. Overlap the fish pieces.

Evenly distribute the remaining vegetables. There is no need to thaw or wash the mix.

A layer of frozen mixed vegetables over sliced onions in a baking dish, drizzled with oil.

Sprinkling vegetables over the onion and drizzling with oil

Seasoned pollock fillets being layered over vegetables in a baking dish.

Arranging a layer of fish and spreading it evenly

A final layer of frozen mixed vegetables spread over the pollock fillets in the baking dish.

Evenly distributing the remaining vegetables


Grate the hard cheese for the casserole on a coarse grater. The cheese should have a medium saltiness.

Crack 3 large eggs and combine them with the grated cheese.

Add smetana (a type of sour cream) and Italian herbs. Do not salt the cheese topping, as the saltiness of the cheese will be sufficient.

A block of hard cheese being grated on a coarse box grater.

Grating the cheese on a coarse grater

Three cracked eggs in a bowl with grated cheese, ready to be mixed.

Cracking 3 eggs and combining them with the cheese

A bowl with eggs, cheese, smetana, and herbs being mixed for the casserole sauce.

Adding smetana and Italian herbs


Pour the cheese mixture over the pollock fillets.

The fish and vegetable casserole being covered with a creamy egg and cheese sauce.

Pouring the cheese mixture over the fish


Cover the baking dish with foil and place it in a preheated oven at 180-190°C (355-375°F) for 40 minutes. Remove the foil after 30 minutes. You’ll know the fish is ready by the appetizing aroma that will fill the room.

The fish casserole, covered with foil, baking in an oven.

Baking the casserole for 40 minutes


Lift the pollock and vegetable casserole with a spatula and transfer it to a plate. The fish casserole will look like a pie that can be cut into pieces of any size.

Your fish casserole is ready. Enjoy your meal!

A slice of fish casserole with vegetables and cheese sauce on a plate, garnished with fresh greens and tomatoes.

The fish casserole with vegetables and cheese sauce is ready!


Serve the casserole with lettuce leaves and fresh tomatoes. You can sprinkle individual portions with flax seeds.

And there you have it—a beautiful and delicious fish casserole, hot from the oven and ready to be enjoyed! This dish is wonderfully versatile; serve it on its own for a complete meal, or pair it with a side of fluffy rice or a crisp green salad. We hope this recipe brings warmth and comfort to your table. Feel free to experiment with different vegetables or cheeses to make it your own. Happy cooking, and enjoy every savory bite!