Preheat the oven to 220°c (200° fan/ 400F/ Gas 6). Line a large baking sheet with baking paper.
Sieve the flour into a large mixing bowl and mix in the bicarbonate of soda and salt.
450 g Self Raising Flour, 1 teaspoon Bicarbonate of Soda, ¼ teaspoon Salt
Rub in the cold cubed butter with your hands until you get fine breadcrumbs. You could also do this in a food processor, but be careful not to over-process the mixture, which would result in tough scones.
100 g Butter
Stir in the caster sugar.
50 g Caster Sugar
Add the buttermilk, vanilla extract, and currants and mix with a metal knife until combined. Use your hands to then bring the dough together.
300 ml Buttermilk, 1 teaspoon Vanilla Extract, 150 g Currants
Shape the dough into a round on a lightly floured work surface to around 4cm thick. Use a 5cm fluted biscuit cutter to stamp out the scones. You'll need to reform the dough a couple of times to get the maximum number of scones.
Place the scones on a lined baking tray and glaze with milk. Bake in a hot oven for 12 minutes or until golden brown.
3 tablespoon Milk