Preheat the oven to 160oC and line 2 baking trays with baking parchment.
Place the drained buckwheat in a glass or stainless steel bowl with the rest of the ingredients (minus the extras), stir well and leave to sit whilst the chia expands.
Meanwhile, spread the coconut flakes on a baking tray and toast in the oven for 8-10 minutes, turning every 2-4 minutes until evenly toasted then set aside.
Reduce the oven to 140oC.
Spread the granola mixture evenly over the prepared trays and bake for about 20 minutes before opening the oven door allow some steam to escape.
Close the door and reduce the temperature to 110oC.
Bake for a further 40 minutes, then remove and gently turn with a spatula to break up.
Return to the oven for final 10 minutes, then remove and cool completely.
Mix the cooled crunch with the extras and store in a glass jar ready to serve.