Roast the hazelnuts

• Preheat the oven to 180 °C.
• Spread the raw hazelnuts on a baking tray and roast, stirring halfway through.

Remove the skins

• While still warm but cool enough to handle, tip the hazelnuts onto a clean kitchen towel.
• Rub them vigorously to remove most of the skins; they don't need to be perfectly clean.

Blend into nut butter

• Add the hazelnuts to a blender and process on low until chopped into small pieces.
• Keep blending while gradually increasing the speed until it looks like nut butter.

Melt the chocolate

• Chop the dark chocolate.
• Melt it in the microwave in short intervals, stirring between each, until smooth.

Finish the spread

• Add the melted chocolate, vanilla extract and sea salt to the blender.
• Blend until fully combined and smooth, then taste and adjust the salt.