You need this:

6 bananas
200 grams of oat flour (100% gluten-free, organic shop) or whole grain buckwheat flour
100 grams finely ground hazelnuts
100 grams of sunflower seeds
a tablespoon of tartaric baking powder
2 tablespoons Green Sweet Extra Sweet
5 drops Green Sweet liquid stevia Natural

For the topping:

2 bananas, cut into nice slices

This is how you make it:

Preheat the oven to 175 degrees, grease a medium-sized cake tin with coconut oil, lined with baking paper.

Puree everything for the cake in a food processor until very fine.

Pour into the can and divide. Top the batter with the banana slices. Bake the cake in the middle of the oven for about 40 minutes, keep checking in between.

Let cool.