Step 1: 1. Preheat the oven to 200°c.
Step 3: 2. Line 2 baking trays with baking paper.
Step 5: 3. In a large bowl, mix the caster sugar and instant coffee together.
Step 7: 4. Place the butter in a saucepan over low heat and heat till boiling.
Step 9: 5. Pour the melted butter into the mixture and leave for 5 minutes without stirring.
Step 11: 6. Add the egg to the butter mixture and beat until it is thick and creamy.
Step 13: 7. Sift the flour, baking powder and ground cinnamon together.
Step 15: 8. Work in the flour into the butter mixture to make a soft dough.
Step 17: 9. Take teaspoonfuls of the dough, roll into balls and place on trays. Flatten slightly with a fork.
Step 19: 10. Bake in the preheated oven for 10-13 minutes.
Step 21: 11. While the biscuits are baking, mix the sugar and cinnamon together to make the cinnamon sugar.
Step 23: 12. As soon as the biscuits come out of the oven sprinkle with cinnamon sugar, allow to cool for a few minutes, and transfer onto a wire rack.