Preheat the air fryer to 200°C (400°F).
Place the flour, baking powder, and cold cubed butter into a large mixing bowl and rub in with your hands until you get a breadcrumb consistency.
175 g Self Raising Flour, ½ teaspoon Baking Powder, 45 g Butter
Mix in the caster sugar.
2 tablespoon Caster Sugar
Heat the milk in the microwave for 30 seconds then add a squeeze of lemon juice and the vanilla extract. Leave to stand for 2 minutes then using a cutlery knife, mix the soured milk into the flour.
85 ml Milk, Squeeze Lemon Juice, ½ teaspoon Vanilla Extract
Bring the dough together with your hands. The dough will be quite sticky and soft at this stage.
Lightly flour your work surface then shape the scone dough into a round disc (roughly 3cm thick) using your hands. Using a 5cm fluted cookie cutter, stamp out 5 scones. You'll need to keep reforming the dough into a disc with your hands until you have used it all up.
Glaze the tops of the scones with a little milk, and then air fry for 7-8 minutes until golden brown and well risen.
Remove the scones from the air fryer basket and cool them on a wire rack for 10 minutes before serving.