Anchovies in Vinegar, Arguiñano Style: Step-by-Step Recipe

Boquerones en vinagre: A tradition made universal by Arguiñano

If there's one chef who has put boquerones en vinagre on the map for millions of Spanish households, it's Karlos Arguiñano. With his direct style, humor, and homemade tricks, Arguiñano has shown time and again that this tapa doesn't require sophisticated techniques or expensive ingredients — just fresh produce, quality vinegar, patience, and a good dressing.

The recipe we share here is inspired by Arguiñano's style: simple, honest, without unnecessary complications but with all the details that make the difference between decent anchovies and memorable ones. Arguiñano himself always insists on the same thing: "with a good product, there's no need to invent anything."

At Bacalalo, since 1990 in Barcelona's Mercat del Ninot, we share that philosophy. We work with the best seafood — from Cantabrian anchovies to Icelandic cod — because we know that raw material quality is everything.

Boquerones en vinagre and Cantabrian anchovies, although they come from the same fish (Engraulis encrasicolus), are two completely different preparations. Boquerones are marinated in vinegar and served fresh, white, and acidic. Anchovies are salt-cured for months and preserved in oil, with a dark color and a deep umami flavor. Both are extraordinary, but this guide focuses on the former.

Ingredients for perfect boquerones en vinagre

This recipe yields a generous tapa portion for 4 people or an appetizer for 2.

For the marinade:

• 500 g fresh anchovies (ask the fishmonger for same-day catch)
• 300 ml white wine vinegar (minimum 6% acidity)
• Coarse salt (not fine, not iodized)

For the Arguiñano-style dressing:

• 4-5 tablespoons extra virgin olive oil (Arbequina or mild Picual)
• 3 cloves garlic, thinly sliced
• A generous bunch of fresh parsley, coarsely chopped
• Salt (optional, to taste)

About the vinegar: Arguiñano recommends white wine vinegar with an acidity of at least 6 degrees. Avoid mild vinegars like Modena, apple cider, or rice vinegar — they don't have enough potency to "cook" the anchovy properly. Sherry vinegar also works, but it gives a darker color and stronger flavor.

Step 1: How to clean anchovies correctly

Cleaning is the most time-consuming step and the one that most determines the final result. Poorly cleaned anchovies will have remnants of guts, bones, or skin that ruin the texture and flavor.

Step-by-step process:

1. Remove the head: Hold the body of the anchovy with one hand and with the other, pull off the head with a downward motion. The guts should come out with the head. If not, remove them with your finger.
2. Open the anchovy: With your thumb, open the anchovy along its belly like a book. Follow the path of the central spine with your finger, separating the two fillets.
3. Remove the central spine: Carefully detach the spine from the tail towards the head. It should come out whole if the anchovy is fresh.
4. Trim: Remove the tail and any remaining fins or loose skin from the edges.
5. Wash: Rinse each double fillet (butterfly style) under a gentle stream of cold water. Do not soak them — they absorb water and lose texture.
6. Dry: Place the fillets on paper towels and gently pat to remove excess moisture.

Arguiñano's tip: "If the anchovy is truly fresh, the spine comes out easily with your fingers. If you have to pull, the anchovy isn't from today." It's an infallible indicator of freshness.

Yield: From 500 g of whole anchovies, you'll get approximately 300-350 g of clean fillets. It's normal to lose 30-40% in heads, spines, and guts.

Step 2: Pre-freezing — safety against Anisakis

This step is mandatory and non-negotiable. Anisakis is a parasite present in fresh fish that can cause severe allergic reactions and intestinal infections. Vinegar alone does not eliminate it.

Safety protocol (according to AESAN and European regulations):

• Freeze the cleaned anchovies at -20 °C for a minimum of 48 hours (5 days if your freezer is 3 stars or less, as it may not reach stable -20 °C).
• Place the fillets in a single layer on a plate or tray covered with plastic wrap. Do not pile them up — they will stick together and break when thawed.
• Label with the freezing date to keep track.

To thaw:

1. Transfer the fillets from the freezer to the refrigerator the night before (8-12 hours).
2. Never thaw at room temperature or with hot water.
3. Once thawed, pat them dry with paper towels before adding the vinegar.

Arguiñano always emphasizes this step in his recipes: "Freezing is not optional, it's common sense. It wasn't done before because Anisakis wasn't known, but now that we know, there's no excuse."

Step 3: The vinegar — time, type, and proportion

Vinegar is what "cooks" the anchovy. Acetic acid denatures the fish proteins, which change from translucent and soft to white, firm, and opaque. It's the same chemical process as heat, but cold.

Procedure:

1. Place the thawed and dried fillets in a glass or ceramic container (never metal, which reacts with the acid).
2. Sprinkle a thin layer of coarse salt over the fillets. The salt helps extract residual moisture and firm up the texture.
3. Completely cover the fillets with white wine vinegar. All fillets must be submerged — if any part sticks out, it will oxidize and turn grayish.
4. Cover the container with plastic wrap and refrigerate.

Marinating times:

• Absolute minimum: 6 hours. With less time, the center of the fillet may remain raw (translucent).
• Optimal time (Arguiñano style): 8-12 hours. The fillets become completely white, firm yet juicy.
• Maximum recommended: 24 hours. Beyond this time, the anchovies start to "over-marinate": the texture becomes soft and mealy, and the flavor becomes excessively acidic.

How to tell if they're ready: Take a fillet and cut it in half. If the center is completely white and opaque, they are ready. If there is still a translucent line in the center, they need more time.

Can the vinegar be reused? No. After marinating the anchovies, the vinegar has absorbed water, proteins, and fats from the fish. Its acidity is no longer the same and it would not be suitable for a second batch. Always discard it.

Step 4: The Arguiñano-style dressing

This is the moment of truth: the dressing that transforms marinated fillets into the tapa we all know and love. Arguiñano's style is clean and direct: garlic, parsley, and olive oil. Nothing more. No onion, no pepper, no frills.

Procedure:

1. Drain the anchovies: Remove them from the vinegar and place them on paper towels. Gently pat to remove excess vinegar. Do not rinse them with water — they would lose the acidic point that defines them.
2. Arrange on a platter: Place the fillets on a shallow dish, arranging them in neat layers with the skin (silver side) facing up. Presentation matters.
3. Dress: Sprinkle the thinly sliced garlic over them. Generously distribute the chopped parsley. Drizzle with a good stream of EVOO — enough to soak the fillets without completely covering them.
4. Rest: Leave the dressed anchovies in the refrigerator for at least 30 minutes before serving. During this time, the garlic perfumes the oil and the flavors integrate.

Arguiñano on garlic: "The garlic should be thinly sliced, not minced. If you mince it, it releases too much juice and can become bitter. Sliced, it provides just the right aroma." It's a small detail that makes a real difference.

Arguiñano on parsley: "Always fresh parsley, never dried. Dried doesn't contribute anything, it's like adding green sawdust. And don't chop it too finely — a coarser chop looks better and has more flavor."

About the oil: Use a mild to medium-flavored EVOO (Arbequina or Hojiblanca). An intense Picual oil can compete with the vinegar and garlic. The oil here has a dual function: to dress and to protect the anchovy from oxidation.

Storage and how long boquerones en vinagre last

Once dressed, boquerones en vinagre are a fresh product and should be treated as such:

• In the refrigerator: They last between 3 and 5 days in an airtight container, covered with olive oil. After the third day, the texture begins to soften and the vinegar flavor intensifies.
• Serving temperature: Take them out of the refrigerator 10-15 minutes before serving. Too cold, the flavor is dulled. At prolonged room temperature, they deteriorate quickly.
• Can they be frozen once made? It is not recommended. Freezing breaks the already marinated structure of the fillet, and when thawed, they become soft and watery.

Signs that they are no longer good: Strong ammonia smell, slimy or mushy texture, yellowish color. If you have any doubt, discard them. You don't take chances with raw fish.

Common mistakes when making boquerones en vinagre (and how to avoid them)

After years of seeing recipes and trying boquerones in bars and homes, these are the most common mistakes:

• Not freezing before marinating: The most dangerous mistake. Vinegar does not kill Anisakis. Pre-freezing is mandatory by law in hospitality and should be at home.
• Too weak vinegar: Vinegars with less than 6% acidity do not "cook" the anchovy completely. Always use standard white wine vinegar.
• Insufficient time in vinegar: 2-3 hours is not enough for normal-sized fillets. If you cut a fillet and see a translucent line in the center, it needs more time.
• Excessive time in vinegar: More than 24 hours produces soft, mealy, and excessively acidic anchovies. 8-12 hours is the optimal point.
• Not drying the fillets before vinegar: Residual water dilutes the vinegar and slows down the marinating process. Always pat dry with paper towels.
• Using metal containers: Vinegar reacts with metal (especially aluminum) and produces unpleasant metallic flavors. Always use glass or ceramic.
• Minced garlic instead of sliced: Minced garlic releases more allicin and can give an excessively bitter and pungent taste. Thinly sliced is the key.
• Serving too cold: Straight from the refrigerator, the anchovies are "asleep" — their flavor is perceived as flat. 10-15 minutes out before serving.

Frequently asked questions about boquerones en vinagre