COOK IT.
Preheat the CUBE charcoal to high heat. Place on the whole red bell peppers and cook, turning every few minutes, until grilled on each side. About 10 minutes in total. Remove from the heat, place into a large bowl and cover with foil or plastic wrap. Allow to sit until cooled.
Remove the red bell peppers from the bowl and peel away the charred skin. Slice off the flesh and discard the seeds. Place the red bell pepper into a food processor with the olive oil and blitz until smooth. Add in the remaining ingredients and blitz until the ingredients come together into a chunky but uniform sauce. Add more olive oil as needed. Set Romesco Sauce aside while grilling the prawns.
Slice the prawns by using a sharp knife to cut from the tail through the middle of the prawn “belly” and to the head of the prawn. Flatten out to butterfly. Place onto the grill and cook for 2 minutes on each side until the prawns are cooked through.
Serve prawns on a platter with Romesco spooned over the top and some parsley leaves to garnish.