Preheat the oven to 180°C and line 2 cookie trays with baking paper
In a large mixing bowl, combine the oats, flour, sugar and coconut. Make a well in the centre.
In a medium saucepan, melt the butter and golden syrup over a medium heat and stir until combined.
Mix the bi carb soda and boiling water together in a small bowl, then add it to the melted butter mixture. It will foam up.
Pour the butter mixture into the dry ingredients, then fold through until well combined.
Using a large ice cream scoop, scoop out mixture. If you press the mixture into the scoop, it will compact and stay together when scooped onto the cookie tray. Leave some space for them to spread a little.
Bake for 10 minutes. Remove from the oven and use a large cookie cutter to twirl them into neat circles (totally optional), then slide cookies onto a cake rack to cool.
Cookies will last in a sealed container for about a week.
