1. Beat the butter, icing sugar and raw sugar until a smooth paste is formed.
2. Add the flour, cinnamon, lemon zest, coconut and salt. Mix until the ingredients form a dough.
3. Press the dough into a flat square, approximately 15mm in thickness, then wrap in plastic wrap and place into the refrigerator to chill for 1-2 hours.
4. Heat the oven to 170°C, fan forced.
5. Press the chilled dough through the grid of a wire cooling rack.
6. Loosely scatter the dough cubes evenly between 12 muffin tin cavities.
7. Bake in the pre-heated oven for 20-25 minutes, until lightly golden.
8. Remove from the oven and immediately grate the milk chocolate over the surface.

Note: Store in an airtight container at room temperature for up to 1 week.