Pre-heat oven to 425°F.
Lightly grease a baking tray; set aside.
In a large bowl, add the flour, baking powder and salt; stir to combine.
Add the butter and rub the mixture between your fingers until it resembles breadcrumbs.
Add the sugar, egg, milk and vanilla (if using); stir the mixture to a soft dough.
Using a lightly floured surface, knead the dough gently and roll out to a 3/4 to a 1-inch thickness.
Using a cookie cutter, cut scones into 2-inch rounds.
Place on greased baking sheet, brush tops with a little milk.
Place in pre-heated oven for 12 - 15 minutes until well risen and golden.