A favourite from Henrietta Green, this watercress recipe is very adaptable.
50g unsalted butter, warmed to room temperature
Small bunch of watercress
Juice of ¼ lemon
Sea salt and freshly ground pink pepper
Method
Mash the butter with a fork in a bowl. Meanwhile pick off the watercress leaves, roughly chop, add to the bowl and mix them in. Add the lemon juice and season to taste - pink peppercorns add a dash of colour but if you don't have any, black ones will do.
Lay out a sheet of foil and spoon on the butter. Roll it into a cylinder, then wrap it up, firmly twisting the ends. Chill - you can even freeze it - and cut into discs as and when required. For maximum effect add the butter just before serving, otherwise it will have melted away by the time you sit down to eat.

Flavoured butter is a great way of perking up a plainly grilled cut of meat or fish. A watercress butter is especially good with steak or a strongly flavoured fish such as cod or pollack but you can make them with virtually any combination of herbs and with or without garlic to go with anything.