1. Preheat the oven to 180 degrees
2. Cut the rhubarb into 1 inch pieces and place in a large dish with ½ of the cider and half of the sugar. Poach in the oven for 15 minutes, or until just soft and still holding its shape. When the rhubarb is poached, strain off the juice and place into a separate saucepan with the rest of the cider and sugar and reduce by 2/3 and cool. Reserve the rhubarb to one side.
3. Meanwhile, toast the oats in a dry frying pan on a medium heat and get a little colour on the oats without taking them too far! Take them out, set aside and allow to cool.
4. Whip the cream into soft peaks. Stir through 2-3 tbsp of the cider syrup, 1 tbsp of whiskey (if using) or more syrup and no whiskey! If you like it a little sweeter add a bit of honey or agave syrup. Taste the mixture and adjust according to your taste.
5. Fold in the oats (reserve a few for the top) and layer up in glasses with cream, then rhubarb. Add a bit of rhubarb and a sprinkle of oats to the top. You can allow to sit in the fridge for ½ an hour before serving to soften the oats or serve straight away.