Turn up oven to 180ºC and line two baking trays with baking paper.
Cream the butter and sugar until smooth. Beat in the egg and vanilla until light and fluffy.
Add in the flour, baking soda and salt mixture, then the coconut and mix until just combined.
Dollop dessert spoons full of dough onto the baking tray, you should fit approx 12 per tray.
Bake for 8 to 10 minutes in the oven, or until lightly golden. Cool on wire racks.
When cookies are cooled, spread caramelised white chocolate mixture onto half and sandwich the cookies together with the remainders.