Pre-heat the oven to 180'C.
Sift together the flour, baking powder, sugar and salt.
Whisk the egg and yoghurt together until smooth.
Rub the butter through the dry ingredients until you obtain a fine crumb texture.
Make a well in the centre of the dry ingredients, and pour in two thirds of the yoghurt. Use a fork to stir gently until you obtain a stiff dough: you may need to add a few more spoonfuls of the yoghurt mix.
When most of the dry ingredients are incorporated into the dough (there should be about 3 tablespoons worth of dry crumbs in the bottom of your bowl), tip everything out onto your work top, and fold the dough onto itself until all the dried bits get mixed in.
Roll out the dough until it is about 1.5cm thick -you may need to lightly flour your table and the top of the dough. Use a 5cm round cutter to form your scones.
Place the scones on a lined baking tray, if there is any of the yoghurt mix left over, brush the top of each scone with it, making sure not to get dribbles down the sides.
Bake for about 12-15 minutes, or until golden brown.
Serve warm with clotted cream and jam.
«It is very important not to over-mix the dough, which is why you want to avoid stirring all the dry ingredients into the dough in one go. Folding the ball of dough onto itself will incorporate the left-over dry ingredients and prevent over-kneading.»