Preheat the oven to 180ºC/350ºF/gas 4.
Line 2 large baking trays with greaseproof paper.
Melt the butter in a small pan over a low heat.
Stir in the golden syrup.
In a small bowl, combine the bicarbonate of soda with 3 tablespoons of boiling water, then stir it into the butter mixture in the pan.
Add the flour, oats, sugar and coconut to the pan of melted ingredients.
Add the vanilla extract and orange zest.
Give the ingredients a good mix.
Place heaped tablespoons of the mixture onto the prepared baking trays, leaving around an inch gap between each one.
Place in the hot oven for around 10 minutes, or until golden.
Move onto a wire cooling rack to cool completely before eating.