Firstly, preheat your oven to 180 C/160 C fan/gas 4, and fold a bit of parchment or baking paper using it to line a brownie tin
On a low heat, melt the butter, sugar, golden syrup and peanut butter together in a large saucepan. Don't be put off by the peanut butter which kind of separates and floats around looking a bit gross - try to ignore that!
When it’s all melted, add the oats and the coconut. Give it a really good stir so that the oats are all properly combined.
Add 100g dark chocolate and mix through
Press the mixture into a brownie tin that’s been lined with baking paper and smooth it over with the back of a spoon.
Bake for 20 minutes. Allow to cool before lifting out of the tin and slicing.