Preheat the oven to 180°C (350°F) and grease an 8"x8" baking pan.
Beat the super soft or partially melted butter, brown sugar and sugar together.
Beat in the egg, vanilla extract and golden syrup.
Mix in the flour, baking powder, salt and cinnamon.
Stir in the white chocolate buttons and M&Ms.
Spread the cookie dough in an even layer in the prepared baking dish and place in the oven to bake for 20 minutes. The middle will still have a few crumbs attached when a skewer is inserted and the outside will be starting to turn golden.