First make the shortbread biscuits. Use your fingertips to gently mix the flour, cornflour, sugar and butter until they bind together to form a stiff ball. Roll out the dough to about 1cm thick and cut with round biscuit cutters. Place the shortbread on a lined baking tray and refrigerate for one hour. Remove from the fridge and place in a pre-heated oven for 20 minutes until just golden. Leave to cool and then dust with icing sugar.
Next place the sliced rhubarb in an ovenproof dish. Put the sugar and ginger into a small pot and add enough water to cover the sugar. Place on a high heat and bring to the boil. Pour this hot sugar and ginger mixture over the rhubarb and place the dish into the hot oven for 20-30 minutes and cook until tender. Remove from the oven and set aside.
Lastly place the rice, vanilla pod, milk, cream, caster sugar and cinnamon stick in a saucepan and cook on a very low heat for an hour and a half, stirring occassionally to ensure that it doesn’t stick.
To serve, put a spoon of warm rhubarb compote in the bottom of a clean glass jar with a lid (or whatever dish you want to use) and then spoon the rice pudding on top. Close the lid and serve on a long plate with three shorbread biscuits.