250g/9oz butter, softened
140g/5oz caster sugar
1 egg yolk
2 tsp vanilla extract
300g/10oz plain flour
Mix the butter and sugar in a large bowl with a wooden spoon, then add the egg yolk and vanilla and briefly beat to combine.
Sift over the flour and stir until the mixture is well combined – you might need to get your hands in at the end to give everything a really good mix and press the dough together.
118 kcalories, protein 1g, carbohydrate 13g, fat 7g, saturated fat 4g, fibre none, sugar 5g, salt 0.13g