Preheat the oven to 300°F /150°C and line a baking sheet with baking paper.
Toss the hazelnuts on the prepared baking sheet and roast for about 10 minutes until fragrant.
Remove the skin while they are still hot. To remove the hazelnut skin after roasting the nuts in the oven, place the hazelnuts in a jar while they are still hot, close the lid, and shake until the skin comes off. Return the hazelnuts to the baking sheet to make sure all the skin has been removed before proceeding with the recipe.
Transfer the hazelnuts to a food processor or blender and pulse until creamy, scraping the sides of the food processor/blender to make sure they are evenly blended. This could take up to 5 minutes.
Add the cocoa powder, oil, powdered Erythritol, vanilla extract, and a tiny pinch of sea salt.
Pulse again to incorporate until smooth and creamy.
Serve at room temperature or store in a sealable jar for up to 2 weeks.