This is one of my wife Carol’s specialities – and it's probably the best shortbread in the world! It’s an old family recipe, and is in Imperial measures,
because that’s how it was handed down from my wife’s Scottish mother! The process has been updated somewhat, though, to take account of modern technology
(food processors!).
Put 8 oz plain flour, 5 oz butter and 2½ oz sugar into a food processor and whizz until it forms a clump. Take the clump out and knead it for a few minutes,
then roll it out on a baking sheet into a disk about 10 inches in diameter. Prick all over with a fork and bake in a 150°C oven for about an hour.
Dust with caster sugar and cut into triangles while still hot, then let it cool.