Preheat the oven to 200 degrees C. Grease two large baking trays.
Melt the butter and syrup in a saucepan over a medium heat. Once melted, remove from the heat and set aside.
Put the oats, sugar, flour and chocolate chips in a large bowl then mix together. Add the butter and syrup and mix well.
Place dessertspoons of the mixture onto the prepared trays, but set well apart, as they will spread to about 8cm. Press down the centres.
Bake in the oven for 8 to 10 minutes, until they just begin to brown on the outsides. The centres will still appear a bit soft. Remove from the oven and allow to cool, about 30 minutes.
Once cooled, drizzle the melted chocolate over the cookies.