Start by pulsing those roasted hazelnuts in a food processor for about 3-4 minutes. You want them to turn into a smooth and creamy hazelnut butter. It might take a bit longer, but keep at it until you achieve that creamy consistency.
Add in the powdered sugar, espresso, vanilla extract, cocoa powder, and a pinch of salt. Blend everything together until it's well combined.
Melt your chocolate and mix it in with a little bit of water.
Blend all the ingredients until you get a nice, smooth texture. Now, you can spread this goodness over toasted bread or enjoy it with some fruit.