Melt the butter in a pan over a gentle heat, and then allow to simmer until you spot the first dark flecks – watch it carefully, or it will burn. Strain through some butter muslin, or two sheets of kitchen roll, into a jug.
Wipe out the pan, and pour in two-thirds of the butter. Add the lemon juice, mace, pepper, anchovy essence and a pinch of salt and simmer very gently for five minutes, then take off the heat and allow to cool but not set. Divide the shrimps between 4 ramekins, pressing them in tightly.
When just warm, but still liquid, divide the spiced butter between the ramekins and put in the fridge to set. Once solid, pour over the remainder of the clarified butter and return to the fridge to set.
Serve with a sprinkle of cayenne pepper and a lot of hot toast.e
