Set your oven to 160°C Fan/180°C/355°F/Gas mark 4
Line your baking sheet with greaseproof paper.
Melt your butter and maple syrup slowly over a a medium-low heat, do not boil.
Sift together your flour, baking powder, cinnamon, cornflour and salt.
Stir in your sugars and oats until equally mixed in.
Stir in your melted butter mixture.
Chop your apple into small chunks no bigger than 1cm and then stir in.
Take a chunk of the mixture weighing 40-43 grams and roll into a ball (or create 15 similar sized balls).
Place on your baking tray leaving a gap of about 3cm between each cookie, so they have room to spread when baking.
Bake in the centre of your oven for 20 minutes, or until the cookies are just starting to brown a little around the edges and the base.
Leave to cool in the tin for a few minutes, then carefully remove to a cooling rack to cool completely.