Summary: Arguiñano-style baked cod is the perfect recipe when you want a spectacular dish without making things complicated. Icelandic cod loins on a bed of confit potatoes, sweet onion, and peppers, all baked at a controlled temperature so the cod is juicy on the inside and golden on the outside. We’ll show you the step-by-step process, with the tricks that make the difference between a decent baked cod and an unforgettable one.
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Arguiñano and baked cod: less is more
Baked cod is one of those dishes that Karlos Arguiñano has prepared countless times on his show, and the reason is simple: it's the perfect demonstration that cooking well doesn't mean cooking complicated. Good produce, correct technique, and the oven does the rest.
The beauty of this recipe lies in the vegetable base. Thinly sliced potatoes absorb the cod juices during cooking, the onion adds sweetness, and the peppers provide color and aroma. Everything cooks at once, in the same dish, creating a complete meal where each ingredient has exchanged flavors with the others.
This version is inspired by Karlos Arguiñano's style, adapted to use premium Icelandic cod loins. At Bacalalo, since 1990 in Barcelona's Mercat del Ninot, we select thick loins ideal for baking: firm, clean-flavored, and with the perfect proportion of flesh and gelatin.
Ingredients for baked cod (4 servings)
For the loins
- 4 Icelandic cod loins (200-250g each, desalted)
- Extra virgin olive oil
- Flaky salt and black pepper
For the vegetable base
- 4 medium potatoes, peeled and sliced 3-4mm thick
- 2 large onions, thinly sliced into rings
- 2 red peppers, cut into strips
- 1 green pepper, cut into strips
- 4 cloves garlic, sliced
- 1 glass white wine (150 ml)
- 200 ml fish stock (or water)
- Extra virgin olive oil
- Salt and pepper
- 1 bay leaf
Premium loins for your baked cod
Icelandic Cod Loin
Thick, firm, perfect for baking — stays juicy without falling apart
Preparing the potato and vegetable base
Preheat the oven to 200°C (390°F) with top and bottom heat. The key to baked cod is that the vegetable base is partially cooked before adding the fish.
Step 1: Assemble the base
Grease a large oven dish with olive oil. Arrange the potato slices in an even layer on the bottom, overlapping them slightly like fish scales. Season with salt and pepper.
On top of the potatoes, distribute the onion rings, pepper strips, and sliced garlic. Add the bay leaf. Drizzle generously with extra virgin olive oil — Arguiñano always says that "olive oil is not an expense, it's an investment."
Step 2: Pre-bake the base
Pour the white wine and fish stock over the vegetables. The liquid should come up about halfway through the potatoes. Cover the dish with aluminum foil and bake for 25-30 minutes until the potatoes are tender when pierced with a knife.
This step is crucial: if you add the cod from the beginning, it will dry out while the potatoes cook. The vegetable base needs more cooking time than the fish.
Baking the cod: times and temperature
Step 3: Add the loins
Remove the dish from the oven and take off the aluminum foil. Place the cod loins on top of the vegetable base, skin side up. Brush the skin with olive oil and season with flaky salt.
If you want extra crispy skin — a touch Arguiñano particularly appreciates — turn on the oven's broiler and place the dish on the top rack for the last 3-4 minutes of cooking.
Step 4: Bake the cod
Return the dish to the oven uncovered for 12-15 minutes at 200°C (390°F). The cod will be ready when the flesh flakes easily when gently pressed with a fork but is still juicy in the center.
Golden rule: Cod continues to cook out of the oven with residual heat. It's better to take it out a little early than to overcook it. A 200g loin needs about 12 minutes; a 250g loin, about 15.
Step 5: Rest
Remove the dish from the oven and let it rest for 5 minutes before serving. The juices redistribute and the cod finishes settling. Drizzle with a final touch of raw extra virgin olive oil and sprinkle with fresh chopped parsley.
Arguiñano's tricks for perfect baked cod
- Pre-bake the potatoes: This is the most important trick. Potatoes need 25-30 minutes, cod only 12-15. If you put them in at the same time, the cod will dry out while the potatoes cook.
- Thin potato slices: Cut them 3-4mm thick with a mandoline or sharp knife. Thick slices won't cook in time and will remain raw inside.
- Fish stock: If you don't have homemade stock, use quality fish stock or even water with a stock cube. The liquid prevents the potatoes from drying out and creates a natural sauce when mixed with the juices.
- White wine: Adds acidity and complexity to the base. It evaporates during cooking, leaving only the flavor. If you don't want to use alcohol, substitute with diluted lemon juice.
- Skin side up: By placing the cod skin side up, the skin toasts and becomes crispy while the flesh remains protected and juicy on the moist bed of vegetables.
- Do not move the cod: Once placed on the vegetables, do not touch it. Every time you move the loin, you lose temperature and break the structure of the flesh.
- Final raw olive oil: A drizzle of raw extra virgin olive oil before serving adds fresh aroma and shine to the dish. Arguiñano calls it "the essential final touch."
Garnishes and accompaniments
Baked cod with potatoes is already a complete dish, but if you want to add something more:
- Green salad: A green leaf salad with lemon vinaigrette cuts through the richness of the dish.
- Crusty bread: For dipping in the juices at the bottom of the dish — the best part.
- Roasted piquillo peppers: If you haven't put them in the base, they are perfect as a side garnish.
- White asparagus: They combine especially well with cod and the white wine from the sauce.
For an exceptional result, the quality of the cod is fundamental. Bacalalo's Icelandic cod loins have the firm texture and gelatin point that the oven needs to produce a juicy and flavorful result, without the dryness that ruins so many baked cod dishes.
Frequently asked questions
At what temperature should cod be baked?
At 200°C (390°F) with top and bottom heat. This temperature is high enough to brown the skin and cook the flesh in 12-15 minutes without drying it out. Lower temperatures produce boiled cod instead of roasted, and higher temperatures dry out the exterior before the interior is cooked.
How long does cod need in the oven?
Between 12 and 15 minutes, depending on the thickness of the loin. A 200g loin needs about 12 minutes; a 250g loin, about 15. Cod continues to cook out of the oven with residual heat, so it's better to take it out a little early.
Can it be made without pre-baking the potatoes?
You can, but it's not recommended. If you put the cod in with raw potatoes, you'll have to bake everything for 40-45 minutes, and the cod will be dry and tasteless. The trick of pre-baking the base is what ensures both the potatoes and the cod are perfectly cooked.
Can I substitute potatoes with sweet potatoes?
Yes, sweet potatoes are an excellent alternative that provides a natural sweetness that pairs very well with cod. Cut them into slightly thinner slices (2-3 mm) because sweet potatoes cook faster than regular potatoes. The pre-baking time is reduced to 20 minutes.
Is it necessary to desalt the cod before baking?
If you use dried cod, yes — desalt it in cold water in the refrigerator for 48 hours, changing the water every 8-10 hours. At Bacalalo, we offer already desalted cod ready to cook, which saves you this step entirely.
Can the potato base be prepared in advance?
Yes, you can pre-bake the potato and vegetable base up to 24 hours in advance. Store it covered in the refrigerator and take it out 30 minutes before baking the cod so it loses its chill. Add a little more stock if all the liquid has been absorbed.




