Preheat the oven to 325 degrees Fahrenheit (160 Celsius) and line a baking tray with baking paper.
Combine the oats, coconut, sugar and flour in a bowl and mix well to combine. Add the melted coconut oil and brown rice syrup and mix. Place the baking soda in a small bowl and add the hot water, and stir to combine. Add to the mixture and mix until well combined.
Form the mixture into small balls (roughly about 1-2 tsp in size). The mixture might be a little crumbly, but should come together when you squeeze it in your hands. Place on the baking tray and flatten well with the heel of your hand and repeat with the remaining mixture, allowing room for the Anzacs to spread slightly.
Bake for 8 to 10 minutes and remove from the oven and allow to cool on the tray for 2 to 3 minutes to firm up before placing on a wire wrack to cool completely.
For chewy cookies err on the side of 8 minutes. For crisper cookies you'll need to bake them closer to 10 minutes. This, of course, will vary slightly depending on your oven and the size of your cookies, and how much you flatten them prior to baking.