You can make your own baking powder by combining 15ml/1tbsp bicarbonate of soda with 30ml/2tbsp cream of tartar. Measure carefully as too much or too little can upset a recipe’s balance.
Bake in the oven for 8–10 minutes, or until golden-brown on top and a skewer inserted into one of the cakes comes out clean. Set aside to cool for 10 minutes, then remove from the tin and cool ...