Preheat oven to 180°C. Brush a 17 x 27cm (base measurement) slab pan with melted butter to lightly grease. Line the base and 2 opposite long sides with non-stick baking paper, allowing it to overhang.
Sift the combined flours into a bowl. Add the oats, coconut, sugar, sultanas and choc bits, and stir to combine. Make a well in the centre and add the melted butter and egg. Use a wooden spoon to stir until well combined. Spoon mixture into prepared pan and use the back of a spoon to smooth the surface.
Bake in preheated oven for 20 minutes or until golden brown and firm to the touch. Remove from oven and set aside to cool completely. Cut into squares to serve.
