Mash the bananas, sour cherries and sultanas with the fruit juice in a bowl with a fork and then stir in the oat flakes. Heat the butter and coconut fat in the microwave a little and gradually add them together with the remaining ingredients.
When the mixture is homogeneous, place on a baking sheet lined with baking paper and spread around 1.5 cm thick in a square so that you can cut the bars well afterwards. Bake in an oven preheated to 175 degrees for approx. 20 minutes until lightly golden. After cooling, place in the refrigerator for at least an hour.
Cut afterwards and wrap the individual bars in cling film. The recipe is enough for 10 relatively large bars. When stored in the refrigerator, the bars should last for at least a week.