Preheat the oven up to 170 degrees of Celcius with a fan function. (Upper and lower heat)
Add oats, buckwheat, and salt to the bowl.
Melt coconut oil and mix with agave syrup.
Pour over dry ingredients and mix it well to make sure all dry ingredients are covered.
Transfer onto a baking sheet lined with baking paper.
Put into the oven and bake for 35 minutes, giving it a stir every 10-12 minutes.
Let it cool down, then add in the berries and chopped dark chocolate.
Transfer into the air-tight container and keep it for two weeks in a cool, dry place.