Preheat the oven to 180C/350F. Spread the nuts on a baking sheet and toast in the oven for 10 minutes. Cool slightly, then roughly chop.
In a large bowl combine oats, melted coconut oil, Manuka honey, Demerara sugar and chopped nuts.
Line a 9" X 13" pan with parchment paper making sure the sides overhang from the pan, then empty the contents of the bowl into the pan, spread evenly and then pack in tightly.
Bake for 20 minutes until slightly golden and smells of honey. Let cool in the pan for 5 minutes, then pick up by the overhanging sides of parchment paper and lift from the pan onto a cutting board. Cut into 16 rectangles. Cool completely and store in an air-tight container.