Place the rolled oats, chopped hazelnuts and flour in a large mixing bowl and stir together.
Place the butter, syrup and sugar in a saucepan and cook over a low heat and stir until it’s all melted. Now pour onto the dry ingredients and mix together. Now place the mixture into a square oven prove dish that has been greased and using the back of a spoon smooth over the surface.
Now bake in a preheated oven of 180oC/350oF/Gas mark 4 for 20-25 minutes until it looks golden brown and feels firm if pressed. Leave to cool in the dish and once cooled cut into squares and serve.