Begin by heating the butter in a small saucepan very gently, then, when it’s melted, remove it from the heat and leave it to cool a little before stirring in the beaten egg.
Now measure the rest of the ingredients into a bowl, pour in the egg-and-butter mixture and stir to a stiff paste. Form the paste into little balls, about the size of a walnut, and place them on greased baking sheets, giving them enough room to spread slightly during the baking, then press them down a little. Bake (one sheet at a time) near the centre of the oven for about 16–18 minutes, by which time the biscuits should feel fairly firm in the centre.
Leave them to cool a little on the baking sheets then remove them to a cooling rack. Store in an airtight tin.
Pre-heat the oven to 180°C, gas mark 4
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