This delicacy is relatively often found in literature but almost never in recipe books. It accompanies the mid-afternoon glass of champagne or tankard of mulled ale admirably. In my view it is best to use Geo Watkins Anchovy sauce, the superior Burgess essence having been sadly discontinued and actual anchovies in salt or oil being for some reason entirely unsatisfactory. I use about a tablespoon per 50g of softened unsalted butter, a pinch of ground mace and the same of cayenne pepper/chilli powder(the white kind if one is lucky enough to have this useful condiment in the house) and mix it all together with some finely scissored chives if they are still growing in the garden. I also add a few drops of truffle oil, this being one of the very few satisfactory destinations for a substance of which it is hard to approve, but I certainly wouldn't buy it in specially. Apply liberally to toasted crumpets. Commercial crumpets are always good, which is very pleasing indeed.