Merluza a la Sidra

Ingredients

Equipment Needed

• •Wide heavy sauté pan or low cazuela with lid, 28 to 30cm
• •Medium saucepan for the potatoes
• •Small lidded pan for the clams
• •Fine-mesh sieve
• •Wide fish slice
• •Instant-read thermometer, optional but useful

Instructions

1. 1

   Purge the clams

   Dissolve the coarse salt in 1 litre of cold water. Add the clams and refrigerate for 1 hour so they can release their grit. Lift them out rather than pouring them into a colander, which would send the sand back over them. Rinse under cold running water and discard any cracked clam or any open one that doesn't close when tapped.

   Many fishmongers sell clams already purged. Even then, give them a rinse and ask when they were cleaned. One gritty shell can spoil the whole sauce.
2. 2

   Par-cook the potatoes

   Put the sliced potatoes in a saucepan, cover with cold water, and add 2g of the fine salt. Bring to a simmer and cook for 7 minutes. They should bend slightly but remain firm in the middle. Drain carefully and spread them on a plate so they stop cooking.

3. 3

   Sear the hake

   Season the hake with 4g of the fine salt and leave it for 10 minutes, then pat the surface dry. Dust with 30g of flour and shake off every loose bit. Heat 30ml of the olive oil in a wide cazuela or sauté pan over medium-high heat. Sear the hake for 1 minute on each side, just until the flour forms a pale golden skin, then lift it onto a plate. The middle must remain raw.

   A light flour coating helps the steaks hold together and later gives the sauce a little body. A heavy coat turns pasty, so shake the fish well. Pésalo, no lo adivines.
4. 4

   Cook the sofrito

   Lower the heat and add the remaining 15ml olive oil. Add the onion with the remaining 2g fine salt and cook gently for 18 to 22 minutes, stirring often, until deep gold, soft, and almost jammy. This is the sofrito, the slow onion base, and its sweetness must come from time rather than high heat. Add the garlic and cook for 1 minute, only until fragrant.

5. 5

   Thicken the base

   Stir in the tomato and cook for 6 to 8 minutes, until it darkens slightly and a spoon drawn through the pan leaves a clear trail. Sprinkle in the remaining 15g flour and stir for 1 minute. It should smell toasted, not raw, without taking on a dark color.

6. 6

   Reduce the cider

   Pour in the cider all at once, scraping the bottom of the pan. Bring it to a lively bubble and cook uncovered for 8 to 10 minutes, until reduced from 300ml to roughly 150ml. Smell it: the raw alcoholic sting should be gone, leaving tart apple and the sweetness of the sofrito. This reduction is the step that decides the dish.

   Use dry sidra natural, not apple juice or a sweet commercial cider. If your substitute still tastes sweet after reducing, stir in the optional 5ml sherry vinegar.
7. 7

   Open the clams

   While the cider reduces, put the clams in a separate lidded pan with 50ml of the fish stock. Cover and cook over medium-high heat for 3 to 5 minutes, lifting each clam out as soon as it opens. Discard any that remain closed. Strain the cooking liquor through a fine sieve to catch the last grit.

8. 8

   Build the cazuela

   Add the strained clam liquor, the remaining 150ml fish stock, and the bay leaf to the reduced cider sauce. Bring to a gentle simmer. Arrange the potatoes across the pan and cook for 5 minutes, turning them once, until almost tender. If the sauce becomes too thick to move around them, add 30 to 60ml water.

9. 9

   Finish the hake

   Nestle the hake steaks among the potatoes and spoon sauce over them. Cover and cook at the gentlest simmer for 5 to 7 minutes, depending on thickness. The flesh should be opaque beside the bone, separate into moist flakes under light pressure, and reach 63°C at its thickest point. Don't boil the sauce hard; hake is delicate and will tighten.

10. 10

    Return the clams

    Add the opened clams and half the parsley. Shake the pan gently by its handles to settle everything into the sauce, then cover for 1 minute, just long enough to warm the clams. Remove the bay leaf, rest the cazuela for 3 minutes, and finish with the remaining parsley. Take the whole pan to the table and spoon plenty of cider sauce over each serving.

Chef Tips

• •Ask for center-cut hake steaks about 3cm thick, preferably with the bone. The bone helps the fish stay juicy and gives the sauce more flavor. The flesh should look moist and pearly, with no strong smell.
• •Frozen hake is a sound choice far from the Cantabrian coast. Thaw it overnight in the refrigerator, drain it well, and pat it thoroughly dry before flouring. It releases a little more water than fresh hake, so the sauce may need an extra minute uncovered at the end.
• •If hake isn't available, use thick pollock loin or cod. Pollock is closer in delicacy. Cod is firmer, saltier, and more assertive, so season it lightly and begin checking it after 5 minutes.
• •Asturian sidra natural is dry, tart, and nearly still. Use a plain dry hard cider if necessary, never apple juice or a cider flavored with berries, spices, or added sweetness.
• •Taste for salt only after adding the clam liquor. Clams can season the entire cazuela by themselves, and extra salt added too early is difficult to take back.
• •Serve the same dry cider used in the pan. Pouring Asturian sidra from height belongs to drinking it, but the bottle for this sauce can go straight into the measuring jug without ceremony.
• •Refrigerate leftovers within 2 hours and eat them the next day. Reheat very gently, covered, only until hot; repeated cooking makes both hake and clams tough.

Advance Preparation

• •The clams can be purged up to 4 hours before cooking. Drain them, cover with a damp clean cloth, and refrigerate; don't leave them submerged in fresh water.
• •The cider sauce can be prepared through the end of the reduction up to 1 day ahead. Cool it promptly, cover, and refrigerate. Reheat gently before adding the stock, potatoes, hake, and clams.
• •The potatoes can be par-cooked up to 4 hours ahead. Cool them in a single layer, cover, and refrigerate.
• •Don't cook the hake or open the clams in advance. Their brief final cooking is what keeps both tender.

Frequently Asked Questions

Nutrition Information

1 serving (about 470g)