SERVES 4
During the 600-year Roman rule of the Iberian Peninsula (from 218 BCE to 409 CE), one of the provincial capitals of Hispania was Tarraco, modern-day Tarragona. It is a lovely spot along the Mediterranean that has long been rich in almond and olive trees. Some historians date Tarragona’s famous romesco sauce to this era. Well, sort of. One of the key ingredients—indeed the ingredient that gives it its name!—is a sweetly mild dried red pepper that didn’t arrive in Spain from the New World until over a thousand years after the fall of the Roman Empire. But as David Solé i Torné wrote in his authoritative book on romesco, the sauce began as a sauce for stewing fish from Tarragona and incorporated the peppers later.
To use the romesco as a stand-alone sauce, eaten cold with grilled vegetables, fish, snails, or—my favorite—dolloped on a hard-boiled egg, stir 1 or 2 tablespoons of red wine vinegar into it. It can be stored, covered in a sealed container in the refrigerator, for up to 1 week.
1. Prepare the Romesco Sauce: Cut the peppers open and remove the seeds. Put the peppers in a bowl, cover with hot water, and soak for 30 minutes; drain. Using a coffee spoon, scrape the soft pulp from inside the skins and reserve. Discard the skins.
2. Stem the tomato, halve crosswise, and seed. Season the face with salt.
3. In a medium skillet, heat 1 tablespoon of the olive oil over medium-low heat. Add the garlic and cook until fragrant, about 1 minute. Transfer to a plate to cool. Place the tomato facedown on the skillet and cook until browned and fragrant, turning from time to time, about 5 minutes.
4. Using an immersion hand blender: Add the romesco pulp, tomato, and garlic to a tall, cylindrical, and narrow container along with the remaining 4 tablespoons olive oil, the nuts, and baguette and season with salt and pepper. Grind, moving the blender up and down, into a moist, gritty paste.
Using a food processor: Add the romesco pulp, tomato, and garlic to the bowl along with the remaining 4 tablespoons olive oil, the nuts, and baguette and season with salt and pepper. Grind into a moist, gritty paste. Wipe down the bowl between pulses to keep the sauce within reach of the blades.
5. Season the fish generously with salt and pepper. In a large cazuela, heavy casserole, heavy skillet, or sauté pan, heat the olive oil over medium-high heat. When the oil begins to shimmer, dredge the fish piece by piece in flour and then cook in single-layer batches, turning only once, until golden on the outsides, 1 to 2 minutes on each side. Transfer to a platter.
6. Pour the wine and then the stock into the cazuela, stir in the romesco sauce, and bring the liquid to a boil. Return the fish to the pan, reduce the heat to medium-low, and gently simmer for 10 minutes, until the fish is cooked through and the sauce slightly thickened. The sauce should be loose but not watery. (If needed, remove the fish and reduce the sauce over high heat. Return the fish to the pan when ready.) Serve from the cazuela.
