Drain the shrimps in a sieve
Clarify about 4ozs butter and return clarified butter to pan.
Add a large pinch of mace, a large pinch of cayenne and a pinch of nutmeg
Swirl spices in butter and add shrimps
Warm gently through but do not allow to boil
Pour into clean dry jar/pot/ramekin and allow to cool.
Chill in fridge.
Remove from fridge long enough before needed for the butter to soften and serve with toast.
In the middle of writing this I remembered that I had seen a big patch of watercress growing in a stream nearby, and I thought it would go nicely with the potted shrimps, so I rushed off to see if I could get some. Sadly the flow of the stream makes it just out of reach without waders so the watercress will have to wait for another day and more equipment!