Ingredients (8-10 servings):
2 kilos of fresh grouper (in slices)
4 large onions, chopped or onion broth
5-6 cloves of garlic (peeled)
5 lemons (about 250 g. of lemon juice)
450 g. of olive oil
Black pepper (as well as some ground black pepper)
1 small bunch of chopped parsley
Rinse the grouper, remove its guts and gills and cut it in slices of 5 to 6 centimeters thickness. Wash the pieces well and carefully remove any blood remaining. Wash them again and put them into a sieve to drain. Sprinkle them with coarse salt. The fish must stay in salt for at least three or four hours, if you haven’t prepared it from the previous day. In the latter occasion, keep the grouper in the fridge, in the sieve and use a tray (usually a baking pan) under the sieve to collect the remaining liquids. Do not remove the grouper’s skin!
Put the slices of grouper on the pan in a way that its entire bottom is covered. It is also recommended to put the grouper’s head together with the slices, because in that way the food will be tastier and the sauce thicker. Add cold water, as much as the fish is covered. Then, put it over very high heat. When it comes to boil, skim it using a skimmer, add the chopped onions, the garlic and pour oil. Alternatively, you can prepare some onion broth with the onions of the recipe. In that case, after you have spread the fish on the pan, sprinkle it with the onion broth, which should be cold and add extra cold water.
Add the black pepper and let the food boil over high heat for about an hour. Then, lower the heat by half and shake the pan occasionally (without mixing with a ladle). When the liquid is less, the sauce starts to thicken. Be very careful with the fish not to stick to the bottom of the pan, especially at the end of the cooking process. Pour the lemon juice thirty seconds before you remove the food from the heat. When you do that, add the ground pepper and the finely chopped parsley and cover the pan with its lid for at least half an hour. The food should always be served using a turner, so as the fish does not fall apart. Carefully pour the sauce on top. It should be served warm, otherwise the sauce gets very thick.
Instructions for the onion broth:
Use the specific amount of onions you need for the corresponding. Rinse them and chop them in big pieces. Boil them in a saucepan with plenty of water over high heat for about an hour. Then, when it gets cold, put the onions and their broth into the blender and mash them. In that way, it turns into a thick liquid, which is called onion broth.