Preheat oven to 180 C/ 350 F and grease/line two large loaf tins.
Combine grated courgette, sugar, sunflower oil, vanilla and eggs in a large bowl. Whisk until combined.
Sift in flour, cocoa powder, salt and cinnamon. Stir with a wooden spoon until just combined.
Fold in dried fruit and nuts.
Spoon into two prepared loaf tins and bake for one hour. Leave to cool on a wire rack.
For the chocolates
Pop your leftover cake in a blender and pulse until it forms crumbs. Transfer to a bowl and set aside.
Combine avocado, maple syrup, coconut oil, cocoa powder and sea salt in a blender and pulse until smooth. You'll need to scrape down the sides of the bowl occasionally. Transfer avocado frosting to a large bowl.
Stir in enough chocolate courgette cake crumbs to make a roll-able mixture.
Roll into 1 inch balls (about 15 grams each) and place on a silicone mat on a baking tray that will fit in your fridge. When all the mixture is formed into balls chill in the fridge for an hour or so.
Break the dark chocolate in a heat proof bowl suspended over a pan of barely simmering water. Stir to melt.
Rest the balls on the tines of a fork and dip into the melted chocolate, allowing the excess to drip back into the bowl. Return to the silicone mat.
When the chocolate has hardened slightly sprinkle with glimmer sugar, if using. Transfer to the fridge to harden completely.
Store the chocolates in the fridge.
Alternatively, the gluten free chocolate courgette cake could be frosted with the avocado frosting!