Prawn cocktail (or shrimp cocktail) is something the Boomers will remember fondly, while wondering whatever happened to it. In the 70s and 80s, this was on menus everywhere and was the de facto starter for many a dinner party. A well-made prawn cocktail is a wonderful thing, and it's actually devastatingly simple to make. This recipe is borrowed from The Prawn Cocktail Years, by Simon Hopkinson and Lindsay Bareham.