You could just use spelt or even avena instead. Add some baking powder and raisins if you like them.
- 2 Bananas
- 60g flour
- 40g raisins (or any other berry, raspberrys are amazing)
- 1-2 teaspoons baking powder
Mix it, form small balls and bake it at 175° for around 15 minutes.
He is always writing that it's necessary to connect them in parallel to make it work. But at the end he's suggesting to wire them like in the picture because it's easier...