Instructions

1. Put the butter and sugar in a mixing bowl, and beat until fluffy. You can do this part with a mixer if you like, or just use your wooden spoon.
2. Add the flour, salt, cayenne, lime zest and juice. Beat with a wooden spoon until combined.
3. Turn dough out onto a lightly floured surface, and gently form into a ball, it will be very crumbly, that is what you want! Flatten to a disc and wrap in plastic wrap, chill in the fridge for 30 minutes.
4. Line two baking sheets parchment paper.
5. Remove dough from fridge and roll out to about 5mm thick. Use a 2"-3" cutter to cut out circles, place on prepared baking sheets. They won't spread so you can put them fairly close together.
6. Prick tops with the tines of a fork (three or four times should do it. Chill cookies in the fridge for another 30-60 minutes.
7. Heat oven to 180C/350F. Bake chilled cookies for 13-15 minutes, until a light golden brown.
8. Leave to cool completely on a wire rack.
9. Melt your chosen chocolate in the microwave in 30 second intervals, stirring in between. Or in a double boiler.
10. Dip one half of each cookie into the chocolate, while it's still wet sprinkle some lime zest on top.
11. Chill for 10 minutes to let the chocolate set, if you can wait!