Preheat the oven to 180°C (350°F). Line a baking tray with greaseproof paper
Cream the butter and the sugar until light and fluffy. Beat in the treacle and egg. Sift in the rest of the ingredients, except the sugar for rolling, and mix everything until combined.
Pour the raw sugar onto a small plate. Portion out teaspoon-sized balls of mixture and roll into balls. Roll the balls into the raw sugar and place on the lined baking tray. Press down on the balls with a fork.