Pre-heat the oven to 350 degrees F.
Line a baking tray with baking paper and spread the sunflower seeds, pepitas, flaxseeds and buckwheat groats out.
Bake the seeds in the oven for fifteen minutes or until nicely toasted.
Combine the psylliam husks, mashed pumpkin, maple syrup, oats, salt, onion powder and coconut oil in a large mixing bowl. Add the cooled toasted seeds and fold through. Add the water and stir well.
Pour the mixture in to a large, lined bread pan and sit covered for at least two hours and up to 24 hours.
To bake, pre-heat the oven to 190 degrees C (375 degrees F) and place the loaf in the oven on the middle rack. Bake for one hour and fifteen minutes. Remove from the oven and allow to cool completely. Store in an airtight container in the fridge for up to a week.