Preheat the oven to 180 ºC.
Bring the apple cider, sugar and cinnamon to the boil in a saucepan to make a syrup. Cook for at least another 10 minutes until you have a thick syrup. Remove the cinnamon stick and leave to cool at room temperature.
Grease a shallow cake mould with extra-virgin olive oil. Crush the biscuits well and add the melted butter. Add to the mould and press down firmly with your fingers to form a firm base.
Beat the eggs and mix in the cream cheese to make a thick, creamy mixture. Add the apple cider syrup and mix all the ingredients together well.
Pour the mixture over the biscuit base and bake until the top turns golden brown (about 45 minutes).
Remove from the oven and leave to cool completely before cutting into individual bars.