For the uninitiated, a biscuit in the USA is closest to a savoury scone, while they call our sweet biscuits ‘cookies’. American supermarkets sell really good instant biscuit mixes, though they are not difficult to make from scratch.
675g/ 12ozself-raising flour, plus more for dusting
Sift the flour into a bowl with the bicarbonate of soda, baking powder and salt. Rub the margarine and butter in gently with your fingertips to achieve a crumb consistency. Stir in the buttermilk with a fork to form a soft dough.