Preheat the oven to 180C/160 Fan/Gas 4. In an ovenproof frying pan, fry the apples and plums in the butter over a medium heat. Add in the honey, water, cinnamon and vanilla and turn down to a simmer. Cook for 7-10 minutes or until thick and sticky. Allow to cool fully.
Cut strips of pastry and arrange over the pan in a lattice style, alternating under and over to create a woven effect. Decorate with leaf shaped pastry around the edge.
Brush with egg yolk and bake in the oven for 20-25 minutes or until golden brown.
Allow to sit for a few minutes before serving.