1. Preheat the oven to 350°F (180°C). Line a baking sheet with baking parchment and set aside. Mix the sugar and lemon zest for the rolling sugar in a small bowl and set aside.

 

2. For the dough add the butter and sugar to a large bowl and mix until light and fluffy. Add the egg yolk and mix until well combined. Add the rosemary and lemon zest and mix in. Mix the flour with baking powder, and salt and add to the bowl – mix until just combined. Shape the dough into walnut-sized balls and roll in the sugar-lemon-zest mixture and place with some space in between on the prepared baking sheet – I could fit twelve on one sheet. Flatten them with the palm of your hand and bake for about 12 minutes. The cookies should get only a light golden color. Take out of the oven and transfer to a wire rack and let cool down completely. Repeat with the remaining dough.