Process biscuits until mixture resembles fine breadcrumbs. Transfer to a large bowl. Stir in sultanas, essence, condensed milk. sifted cocoa and coconut. Mix until well combined. Cover and refrigerate for 30 minutes.
Roll 2 level teaspoons of mixture into balls. Place onto a tray lined with baking paper. Refrigerate for 30 minutes.
Using a fork, dip each ball into melted white chocolate. Place on a wire rack. Decorate tops with red and green glace cherries to resemble holly. Refrigerate until set