Coat glasses with oil. Preheat the oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Cream butter, sugar and cinnamon with the whisks of the mixer. Stir in eggs one at a time.
Stir in flour, baking powder and starch.
Wash, peel, quarter, core and grate the apple. Add raisins to the dough. Simmer lid and preserving rings in boiling water for 2 minutes, then drain. Remove the cakes.
Close jars immediately with preserving rings, lids and clips. Leave to cool.