Rodaballo

Ask the fishmonger to gut it, then roast it skin-side down in a lightly oiled dish at 200°C for about 25–35 minutes, depending on its size. It is ready when the flesh is opaque and separates easily from the backbone; check the thickest part reaches 63°C.

Yes. Grill thick, skin-on portions over medium heat, skin-side down first, until the flesh is opaque and flakes easily; turn them briefly to finish. Keeping the skin on helps protect the delicate flesh from the heat.

Keep it covered in the coldest part of the fridge and cook it within a day or two of buying. For longer storage, wrap it tightly and freeze it; thaw it overnight in the fridge before cooking.

Grilled turbot is often served with a simple garlic-and-vinegar dressing, as in turbot à la Donostiarra. New potatoes, steamed greens or a crisp salad make good accompaniments without masking its mild flavour.

Brill is the closest practical substitute: it is another firm, flat fish and works well in the same recipes. Halibut also suits roasting or grilling, though its thicker fillets may need longer to cook.

The flesh should turn opaque and separate into flakes when nudged with a fork. For a reliable check, insert a food thermometer into the thickest part and cook until it reaches 63°C.