Remove the apple seeds by only taking out the central part, leaving the apple peel intact. Make sure to wash them thoroughly in the end.
Add a large spoonful of plum marmalade to the hole where the seeds were removed. If you don't like the mentioned marmalade, you can choose another one.
Place the apples in a baking dish on parchment paper and bake them at 180 degrees Celsius. Bake for approximately 30 minutes. The apples are done when they become soft.
Optionally, you can also add ground nuts to the marmalade according to your preference.