Melting Moments would have to be my favourite biscuits of all time. They aren't sickly sweet but have just enough sugar in the filling to appease the dessert gods. While I'm fond of the vanilla version which is what you find in most cafes and bakeries I live for Chocolate Melting Moments.
The recipe is from taste.com of course. I changed the filling to passionfruit icing (frozen from my Dad's home-grown passionfruit). I beat 3 tablespoons of butter with 3 cups of icing sugar and kept adding passionfruit pulp until I had the right consistency to join the melting moments. The chocolate and passionfruit combination seems to work well as a bit into these biscuits is like a hint of sunshine on a wintry, rainy day.