Cod au gratin with mayonnaise

Cod is a very versatile fish, so that many elaborations can be prepared from it. In this case, we will cook cod gratin with mayonnaise, a simple, healthy and tasty recipe.


Cod is a fish with an excellent nutritional composition. It is characterized by a low caloric content providing 78 calories per 100 grams. Regarding fats, we can say that it is low in fat and rich in omega 3 fatty acids.

The protein content exceeds that of other fish in the same group. So it is a fish with great characteristics for weight loss or for athletes.

Preparation of cod gratin with mayonnaise

Ingredients for 4 people

  • 4 Loins of fresh and desalted cod. It can also be prepared with frozen or salted cod. In the case of using salted cod, it must be desalted immersing it in water for two days and changing the water 2-3 times a day.
  • 1.2 kilograms of potatoes
  • 2 ripe tomatoes
  • 1 egg.
  • Extra virgin olive oil
  • Salt.
  • Vinegar or Lemon

Mayonnaise elaboration

For the elaboration of cod gratin with mayonnaise, It is necessary to make a homemade mayonnaise with a quality fat, which is extra virgin olive oil. It can also be made with sunflower oil, but, at the level of nutritional quality, olive oil is better.

If we want the flavor of the mayonnaise is not very strong, we can use varieties of extra virgin olive oil as is the arbequina or arbasona.

The steps to follow for make homemade mayonnaise They are as follows:

  1. Pour the egg, vinegar or lemon and salt to taste into the blender glass.
  2. Beat and, when the ingredients are well mixed, we are adding extra virgin olive oil little by little so that it emulsifies, but without making up and down movements
  3. Once the sauce is emulsified, movements can be made from top to bottom.
  4. Once cast the mayonnaise, we separate it until its use is necessary.

Cod fillet au gratin with mayonnaise

  1. First, let's preheat the oven to 180 ° C. Peel and wash the potatoes and cut them in a bakery way.
  2. In a glass dish, put a tablespoon and a half of extra virgin olive oil and place the potatoes. We put them in the oven to make them, since they take longer than cod.
  3. Later, we grate the tomatoes. When we see that the potatoes are soft, we add the grated tomato and introduce the cod loins on the tomato and potato bed.
  4. We leave the cod about 10 -15 minutes in the oven. Meanwhile, we make the mayonnaise.
  5. When we see that the cod is at its point, we add the mayonnaise above the cod loins.
  6. We turn on the oven grill and reintroduce the glass dish with all the ingredients.
  7. Leave the cod in the oven until we see that the top begins to brown.
  8. We take it out of the oven and … voilà!

We have already prepared an excellent dish of Cod au gratin with mayonnaise.