Knead cold butter into pieces, flour, egg yolk, sugar and cold water. Roll out on flour (approx. 12 x 14 cm), cut into 12 strips (approx. 1 x 14 cm), weave into a grid and cut into 4 squares. Keep cold.
Wash the apples, cut off the lid, hollow out the apples slightly, remove the seeds. Cut the lid and the flesh into small pieces. Mix with raisins, pine nuts, sugar, lemon juice and rum. Fill apples, place grating on top, press on. Decorate with cinnamon sticks. Bake at 200 °C (convection oven: 175 °C/gas: see manufacturer) for about 35 minutes. Goes well with vanilla ice cream.