Step 1Heat the oven to 400 degrees. Line a jellyroll pan with aluminum foil. Bake the hazelnuts until they are fragrant, about 10 minutes. Remove to a kitchen towel and rub them in the towel to remove as much of the papery peel as you can.
Step 2Add the almonds and the tomato to the pan and return it to the oven. Remove the almonds when they are fragrant, about 5 minutes, and continue roasting the tomato, turning after another 5 minutes, until it is beginning to char and soften, 20 to 25 minutes in all. Leave the oven on if cooking the cauliflower steaks immediately.
Step 3In the meantime, cover the chile with boiling water and set aside to soften. Heat 2 tablespoons olive oil in a medium skillet. Add the bread and fry until lightly golden on both sides, about 2 minutes per side. Remove from heat and transfer the bread, leaving the oil in the pan, to a food processor. Discard the oil.
Step 4Add the garlic, hazelnuts, almonds, tomato, chile, pimenton and three-fourths teaspoon salt to the food processor and pulse until finely ground. Add three-fourths teaspoon red wine vinegar and with the processor running, pour in the remaining tablespoon olive oil in a stream to make a thick, chunky cream. Thin the sauce, if desired, with water, pulsing in a little at a time. Season to taste with more salt and vinegar if necessary.
Step 5Romesco is served at room temperature. This recipe makes about 1 cup sauce, more than is required for the dish. Store the remainder tightly covered in the refrigerator for up to a week.
Step 1Heat the oven to 400 degrees and line a jellyroll pan with aluminum foil. If you have just made the romesco sauce, you can use the same pan.
Step 2Trim away the leaves of the cauliflower and enough of the base to allow it to sit flat on the cutting board. Leave as much of the core as you can, as this is what will hold the cauliflower together during cooking.
Step 3Using a very sharp knife, cut the cauliflower into half-inch vertical slabs, working from the center out for the largest steaks. You should have four steaks; save any remaining cauliflower for another use.
Step 4Heat the oil in a large nonstick pan over medium-high heat and add the whole, peeled garlic clove. Cook the garlic until it is light brown and blistered and then discard the clove.
Step 5Cook the cauliflower steaks two at a time, frying on each side until lightly browned, about 2 minutes per side. When the underside begins to brown, sprinkle the top with salt and flip the steaks over. Be very careful turning as the cauliflower is delicate and will want to break apart; using 2 spatulas is a good idea. When the second side is browned, sprinkle with a little more salt and transfer them to the jellyroll pan.
Step 6When all the steaks are browned, roast in the oven until they are quite tender, 15 to 20 minutes.
Step 7Spoon a couple tablespoons of romesco on the serving plate where the stem of the cauliflower will be. Place the cauliflower, browned side up, on the plate over the sauce and serve immediately, passing the remaining sauce at the table.