Prepare a flat baking sheet by lining it with tin foil or parchment paper. You won't be baking these nuts, but you will need to use something to lay them flat on that will also fit in your freezer.
In a bowl add your cinnamon and carob powder. Next slowly add your maple syrup and a little at a time and mix continually to prevent it going lumpy. Mix until it is smooth and glossy.
Add your walnuts to your chocolate sauce mix and stir gently to cover every nut.
Spoon your mixture out onto you prepared lined tray evenly, then put in your freezer to set.
You can eat your chocolate-cinnamon spiced walnuts straight from the freezer as the chocolate does not set hard. This also helps keep them fresh.