Preheat the oven to 220°C (fan oven 200°C), gas mark 7.
Sift the flour and baking powder into a bowl and rub in the butter until the mixture resembles breadcrumbs.
Stir in the lavender sugar (sifted if preferred) and a pinch of salt and make a well in the centre of the flour mixture. Pour in the buttermilk and mix to combine, making a soft dough.
Briefly knead the dough on a floured surface, then lightly roll out to about 2cm (3/4in) thick. Cut scones with a 6cm (2.5in) pastry cutter and place on a greased baking sheet.
Brush the top of each scone with a little extra buttermilk and bake in the preheated oven for 12-15 mins, until lightly browned on the top. Cool on a wire rack, dust lightly with flour and serve with your favourite choice of Bonne Maman Conserve.
To make lavender-flavoured sugar, push 2-3 small washed and dried sprigs of fresh lavender into a jar of caster sugar. Leave for at least 24 hrs before using.
Any flavoured sugar can be used in the scones; try cinnamon and serve the scones with Raspberry Conserve and clotted cream.
If you cannot find buttermilk, use some sour whole milk instead.
Brushing the scones with beaten egg before baking will give them a shiny golden top.