Preheat the oven to 160C (140C fan forced).
Line two large trays with baking paper.
Place the rolled grains, nuts, sunflower seeds, pepitas, and coconut in a large bowl. Stir through to combine.
Add the cinnamon, nutmeg and salt. In a separate bowl, place the coconut oil and the maple syrup and whisk to combine. Stir again to mix the spices through the grains.
Place the melted coconut oil, rice bran syrup and maple syrup into a small bowl or jug. Add the vanilla extract then stir until combined. The mixture will seem to thicken and emulsify.
Pour the liquids over the dry ingredients and stir until the muesli seems slightly damp.
Spread the mixture onto the lined trays.
Bake for about 30 - 40 minutes, stirring the edges of the mixture into the middle every 5 -10 minutes to ensure even baking.
Watch the muesli carefully towards the end of the baking time and check more frequently as it can burn easily.
When golden brown, remove from the oven and allow to cool.
Store in an airtight container.