Preheat oven to 160 degrees celsius (fan-forced). Grease and line three flat baking trays with baking paper.
Combine the rolled oats, flour, brown sugar and coconut in a bowl.
Place butter, golden syrup and 2 tablespoons cold water into a microwave-safe bowl and heat for 3 minutes, 50% power or until melted.
Stir through the bicarbonate of soda.
Pour the butter mixture over the oat mixture and stir to combine.
Roll level tablespoons of mixture into balls.
Place on trays, 5cm apart and flatten slightly.
For chewy ANZACS, bake for 10 to 12 minutes or until light golden. For crunchy ANZACS, increase cooking time to 12-15 minutes.
Leave on the baking trays for 5 minutes before transferring to a wire rack to cool completely.