Gooey Apple Crumble Cookie Bars with White Chocolate Chips, Apple, and Crumble goodness!
Preheat your oven to 190C/170C Fan, and line a 9x9inch square tin with parchment paper and leave to the side for now.
Whisk the Flour, Bicarbonate, Salt, Cornflour and Cinnamon together so its evenly distributed, and leave to the side.
In a large bowl, melt the butter. Add in the two sugars and whisk for 2 minutes until the sugar starts to to dissolve and the mixture becomes smoother.
Add in the Vanilla and Egg and whisk again briefly to combine.
Add in the dry ingredients, the apple, and the chocolate chips and mix together till a thick cookie dough is formed.
Press down into the prepared tin.
Make the crumble by rubbing together the Flour, Butter and sugar until fine crumbs are formed, and then sprinkle over the top of the cookie dough.
Bake the Cookie Bars in the oven for 25-30 minutes, or until golden. The less the time, the gooier they will be.
Leave the cookie bars to cool for 10 minutes in the tin, and then finish cooling on a wire rack.