With your butter at room temperature, add the sugars and beat together until creamy.
Add eggs and vanilla, stir to combine.
Add flour, baking powder, and baking soda. Stir the baking powder and soda in to the flour a little bit to mix before adding cinnamon and salt.
Stir until mixed thoroughly.
Add coconut, oats, and chocolate chips. Stir until combined.
Line two cookie sheets with baking paper. Drop mix by tablespoonsful onto the paper. (the original recipe says 1/4 cup of cookie dough, which would make some huge cookies. They'd be good though!)
Bake for 10 minutes and check - if they look very brown, take them out. If they are still pale-ish, swap the cookie sheets over and cook a further 5 minutes until golden brown. Overcooking will make them crunchy, and these cookies really are at their best when chewy.
Leave to cool on the sheet for a minute or two before transferring to a wire rack.