Preheat the oven to 200C (fan).
Using a blender, pulse the oats and the buckwheat groats until ground into flour (it should take approx. 20 to 60 seconds depending of the power of your blender). Set aside.
Using a large mixing bowl, mashed the bananas with a fork.
Add the dates pieces to the bananas mixture and mix well. Set aside.
In a small bowl, mix well the chia seeds with the milk and add straight away to the bananas and dates mixture. Mix them together until homogeneous.
Add to your mixing bowl (bananas, dates, chia and milk) half of the flour first, the baking powder and cinnamon. Mix well with a wooden spoon. Add the remaining flour and mix again.
Prepare a rectangle baking pan, lined with waxing paper and pour your bread mixture.
Optionally, add the topping of your choice : few slices of banana, some vanilla powder. Brush the top with a bit of maple syrup.
Reduce the oven to 180C (fan) and bake for 35 minutes. Take it out of the oven and let it cool down. This bread is deliciously moist and great with your choice of chocolate paste, peanut or any nut butter !