Place the red peppers on a baking sheet and place them under the grill in the oven. Let them scorch on all sides and then place them in a bowl with film around. Leave for 7-10 minutes. The steam from the hot peppers will loosen the skin on the peppers. Remove the skin, stems and seeds from the pepper and place in a bowl with the remaining ingredients except bread, vinegar and half of the olive oil. Blend with a hand blender until it is a uniform mass. If needed add more oil in the process. Season with vinegar. If the salsa is very wet, you can use the dry bread to give it a slightly firmer consistency.
If there’s any romesco salsa left, it also does incredibly well as spread in a sandwich.