Fish Gratin in Tomato Sauce
By Culiora

A succulent fish bake featuring mild white fish baked in a rich tomato sauce seasoned with garlic, herbs, and cream. Topped with grated cheese and broiled until golden brown in the oven, this simple weeknight dinner pairs perfectly with boiled potatoes or rice.
- Servings: 4
- Prep time: 15 min
- Cook time: 30 min
- Total time: 45 min
Ingredients
- 600 g cod or saithe fillets, cut into portion-sized pieces
- 1/2 tsp salt
- 1 pinch freshly ground black pepper
- 1 pcs yellow onion, finely chopped
- 2 clove garlic cloves, finely chopped
- 1 tbsp olive oil or butter for frying
- 400 g good-quality crushed tomatoes
- 2 tbsp tomato paste
- 1 dl heavy cream or cooking cream
- 1 tsp dried oregano or thyme
- 1 pcs fish bouillon cube, crumbled
- 1/2 tsp granulated sugar
- 1/2 tsp salt
- 1 pinch freshly ground black pepper
- 150 g aged cheese (such as Prästost, Herrgård, or Cheddar), grated
- 2 tbsp fresh parsley, finely chopped
Instructions
- Preheat the oven to 200°C (conventional heat). Grease a baking dish, approximately 20x30 cm.
- Heat the oil or butter in a saucepan over medium heat. Sauté the finely chopped onion for 3–4 minutes until softened without browning. Add the garlic and tomato paste, stirring constantly for another 1 minute.
- Pour in the crushed tomatoes, cream, crumbled fish bouillon cube, oregano, and granulated sugar. Bring the sauce to a boil and let it simmer over low heat for 8–10 minutes to allow the flavors to develop. Season to taste with salt and black pepper.
- Pat the fish pieces lightly dry with paper towels. Season the fish all over with 1/2 tsp salt and 1 pinch black pepper, then arrange the pieces in an even layer in the baking dish.
- Pour the warm tomato sauce evenly over the fish and sprinkle with the grated cheese.
- Bake in the center of the oven for 18–20 minutes, until the cheese is nicely browned and the fish is just cooked through (internal temperature of 50–52°C).
- Remove from the oven, sprinkle with freshly chopped parsley, and let the gratin rest for 5 minutes before serving.