Step 1

Line the base and two sides of a 20cm x 20cm square baking tin with baking paper allowing the paper to overhang to form handles (this makes slice easier to remove from the tin).

Step 2

Process the biscuits and coconut in a food processor until crumbs, keeping some texture. Transfer to a large bowl.

Step 3

Combine condensed milk and butter in a small saucepan and cook, stirring occasionally, until butter has melted, and mixture is cohesive and smooth. Add condensed milk mixture to biscuit mixture with the zest and juice and stir until well combined. Spoon mixture into prepared tin and firmly press into tin using the back of a spoon. Refrigerate for 3-4 hours or until firm.

Step 4

To make the icing, combine the icing sugar, butter and lemon juice in a medium bowl until smooth and a spreadable consistency. Spread icing over slice and sprinkle with lemon zest. Cut into 16 squares to serve.