Also known as patum peperium, this stuff is more English than Hugh Grant eating Marmite on toast. This is a damned good recipe, I actually prefer it to the real thing. If you like anchovies I suggest giving it a try!
http://www.food.com/recipe/patum-peperium-the-secret-is-out-gentlemans-relish-228778
http://www.food.com/recipe/patum-peperium-the-secret-is-out-gentlemans-relish-228778