Preheat the oven to 180°C. Dust a large baking sheet with a little cake flour.
1. Mix the cake flour, baking powder, salt and poppy seeds (if using) in a large mixing bowl.
2. In a separate bowl, whisk the yoghurt or buttermilk and eggs together, then add to the flour mixture. Mix until a soft dough has formed. Knead lightly until smooth.