Berasategui Style Fish Soup: Recipe with Cod and Seafood

Berasategui and Fish Soup: Elevated Basque Tradition

In Basque cuisine, fish soup is not just any first course: it is a statement of principles. Martín Berasategui, born in San Sebastián and trained in Spain's most demanding culinary tradition, has made this dish one of his hallmarks. With 12 Michelin stars spread across all his restaurants, Berasategui knows that the greatness of a soup lies in its broth.

Berasategui's philosophy for soups is clear: a well-made fumet is 80% of the success. There are no shortcuts – if the broth is bland, no last-minute ingredient will save it. Therefore, his technique focuses on extracting the maximum flavor from each element: toasted carcasses, sweated bones, confit vegetables, and a patient reduction that concentrates all the aromas of the sea.

This recipe is inspired by Martín Berasategui's style, adapted for home cooking but without sacrificing any essential steps. We use Icelandic cod from Bacalalo as the protagonist, a product that, due to its clean flavor and firm texture, adds body and elegance to the broth.

The Fumet: The Base of Everything

A fumet is a short fish broth, more concentrated and aromatic than a normal broth. The difference lies in the prior toasting of the carcasses and a controlled cooking time: too little and the broth is bland; too much and it becomes bitter from the bones.

Berasategui uses a mix of rock fish (scorpionfish, monkfish, redfish) with crustacean shells (shrimp, prawns, Norway lobster) to achieve a broth with depth and complexity. The crustacean shells provide a natural orange color and a seafood flavor that elevates the soup above any basic fumet.

Complete Ingredients (6 servings)

For the fumet

• 1 kg fish carcasses (monkfish, hake, scorpionfish — ask at the fishmonger's)
• 500 g shrimp heads and shells
• 2 leeks, cleaned and sliced
• 2 carrots, sliced
• 1 large onion, quartered
• 3 ripe tomatoes, halved
• 4 cloves garlic, crushed
• 1 glass white wine (200 ml)
• 1 sprig parsley
• 1 bay leaf
• 10 black peppercorns
• 3 liters cold water
• Extra virgin olive oil

For the soup

• 300 g desalted Icelandic cod, in 3 cm pieces
• 12 fresh shrimp (reserve shells for the fumet)
• 500 g mussels, cleaned and de-bearded
• 1 red bell pepper, finely diced (brunoise)
• 2 tablespoons tomato paste
• Fresh chopped parsley
• Toasted bread for serving

Fumet Preparation Step-by-Step

Step 1: Toast the Carcasses

In a large pot, heat a drizzle of olive oil over high heat. Add the fish carcasses and shrimp shells. Toast for 5-7 minutes, stirring, until the carcasses are golden and fragrant. Berasategui considers this toasting step fundamental: the Maillard reaction in the carcasses adds depth and color to the broth.

Step 2: Aromatic Vegetables

Add the onion, leek, carrot, garlic, and chopped tomatoes. Reduce the heat to medium and sauté for 10 minutes, stirring so that the vegetables absorb the juices from the carcasses. The vegetables should soften and begin to release their juices.

Step 3: Deglaze and Cook

Pour in the white wine and scrape the bottom of the pot with a wooden spoon to release any caramelized bits stuck to the bottom. Let the wine reduce for 2 minutes. Add the cold water, parsley, bay leaf, and peppercorns.

Increase the heat until it comes to a boil, then reduce to a gentle simmer. Cook for 40-45 minutes over low heat, with the pot half-covered. Do not cook for more than 45 minutes: the bones start releasing bitter substances after that time.

Step 4: Strain and Reduce

Strain the fumet through a fine-mesh sieve or cheesecloth, pressing lightly on the carcasses with the back of a ladle to extract the last juices. Discard the solids. You should have approximately 2 liters of fumet.

If you want a more concentrated flavor (as Berasategui does), reduce the fumet over medium heat until you have 1.5 liters. The broth should have a golden-orange color and a deep sea aroma.

Assembling the Soup and Cooking the Fish

Step 5: The Soup Base

In a clean pot, heat 2 tablespoons of olive oil over medium heat. Sauté the finely diced red bell pepper for 5 minutes. Add the tomato paste and cook for 2 more minutes. Pour in the hot fumet and bring to a gentle boil.

Step 6: Cook the Seafood

Add the cleaned mussels to the simmering soup. Cover and cook for 3-4 minutes until they open. Remove the opened mussels with a slotted spoon and set aside. Discard any that have not opened.

Add the pieces of desalted Icelandic cod to the broth. Cook over low heat for 5-6 minutes. The cod from Bacalalo has the perfect firmness to hold its shape in the broth without falling apart.

In the last 3 minutes, add the peeled shrimp. They cook quickly and should not be overcooked or they will become rubbery.

Step 7: Reincorporate and Serve

Return the mussels to the soup. Season with salt to taste. Sprinkle generously with fresh chopped parsley.

Berasategui's Tricks for an Unforgettable Soup

• Toast the carcasses: This step makes the difference between a homemade fish soup and a restaurant-quality one. Toasting creates complex flavors that water alone would never extract.
• Shrimp shells: Never throw them away. Shrimp shells are the most underrated source of flavor in Spanish cuisine. Freeze them if you don't use them immediately.
• Just the right cooking time: 40-45 minutes for the fumet, no more, no less. More time extracts bitterness from the bones. It's a common mistake to think that more cooking = more flavor.
• Cold water at the start: Always start with cold water. Cold water gradually extracts flavors; hot water seals proteins and traps flavor within the carcasses.
• Reduction for concentration: If the broth lacks intensity, reduce it. Better 1.5 liters of intense broth than 2 liters of watery broth.
• Cook each protein separately: Mussels first, then cod, then shrimp. Each has a different cooking time, and putting them all in at once leads to disaster.
• Do not boil vigorously with fish inside: Once you add the cod and shrimp, the soup should be at a gentle simmer. Aggressive boiling breaks down the flesh and makes it dry.

Presentation and Serving

In Berasategui's style, the soup is served in preheated deep plates:

• Distribute the pieces of cod, shrimp, and mussels on the plate
• Pour the hot broth with a ladle, partially covering the ingredients
• A drizzle of extra virgin olive oil in a spiral over the broth
• Fresh chopped parsley and optionally a few drops of lemon
• Toasted bread rubbed with garlic as an essential accompaniment

For a more spectacular presentation, you can serve the broth separately in a small pitcher and pour it at the table over the ingredients already arranged on the plate. This is a theatrical trick Berasategui uses in his restaurants.

Frequently Asked Questions