An aromatic butter is useful to have in the fridge or freezer. I make a decent-sized batch, using some immediately to savour a grilled vegetable or piece of meat, storing the rest, tightly wrapped, for another day. If you only want enough for this recipe, make half the quantity.
Beat 200g of unsalted butter to a soft, spreadable cream. Dry 8 anchovy fillets with kitchen paper to remove their oil, then chop them finely and stir into the butter. Finely chop 1 tbsp of thyme leaves.
Chop 150g of stoned green olives finely, then mix them and the thyme leaves into the butter, grind in some black pepper, then roll into a tubby cylinder and wrap in greaseproof paper or kitchen film and refrigerate or freeze until needed.
To make the mushrooms, warm 4 tbsp of olive oil and 2 tbsp of water in a wide sauté pan, then snuggle 6 large flat mushrooms into the oil. Tuck in 2 garlic cloves, peeled and sliced in half. Cook over a moderate heat until lusciously tender for about 8-10 minutes, covered by a lid.
Lift the lid, check the mushrooms for doneness with a skewer or point of a knife, then pour in a splash of dry sherry if it takes your fancy and let it bubble for a minute. Melt a couple of thick slices of the olive butter in the pan, spoon the pan juices over the gills of the mushrooms, then lift out and pile on to a couple of rounds of thick, hot toast, or a fragrant mound of steamed brown rice.
The butter, with its notes of thyme, olive and anchovy, is really useful. The subtle anchovy means it is especially good with grilled lamb cutlets – brush with the melted butter as they cook.
This butter is an asset to have in the freezer. Store it wrapped in greaseproof paper and foil, to slice as needed. The butter, melted, is a splendid option in which to toss steamed purple sprouting broccoli or cauliflower.
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