Pre heat the oven to 160 degrees fan and prepare a baking tray lined with greaseproof paper.
Thinly slice the 2 red apples and remove all pips - the thinner they are the more crisp they will be after baking. Slice straight through removing any stalk or pips as you go. I slice mine at a 90 degree angle to the core, to allow for a star shape in the centre of the crisps where the pips were.
Place the sliced apple on the lined baking tray. Try not to overlap the slices as they will stick together during baking. Sprinkle over ½ tsp ground cinnamon then bake in the oven for 30 minutes or until crisp. Check them regularly as they will burn quicker than you think. Also as check and remove the smaller thinner ones as necessary as they will bake and crisp up quicker.
When crisp, remove from the oven and set to one side to cool. Do not refrigerate as they will go soggy.
To make the stewed apples:
Whilst the crisps are baking, start preparing the baking apples. Peel and core then slice into chunks (around 1 cm cubed in size). Place a large pan on a medium heat and add the butter. As the butter starts to melt add the chopped apple and golden sugar. Stir well until the sugar dissolves. Pop on a lid and allow to simmer for 5 minutes of so - check and stir regularly. As soon as the sugar starts to caramelise (turns darker brown) and the apples become soft, remove from the heat. Transfer to a bowl and set to one side to fully cool. Place in the fridge to chill until ready to serve.
To make the bircher:
While the crisps and stewed apples are cooling, prepare the bircher. Place the oats, yogurt, apple juice, sultanas and cinnamon into a mixing bowl and stir together until well combined. Add a little more yogurt or apple juice if the mix appears to dry or stiff. Chill in the fridge for at least 10 minutes or until ready to serve or overnight if you have time. (I usually transfer the bircher to a piping bag and secure with a peg before chilling. Piping the bircher on when serving is so much easier and neater)
Putting the dessert together.
Once the stewed apples are fully chilled the dessert can be put together. This only takes 5 minutes and so for the freshest of finishes I tend to build these desserts just before I serve them. Line up your serving glasses/pots. Spoon the stewed apples into the bottom of each glass - fill them to about half way. Next pipe or spoon the bircher onto the top of the stewed apples. Top each glass with a couple of apple crisps and sprinkle over the chopped hazelnuts. Serve with extra apple crisps on the side.