Heat your oven to 350°F (176°C). Place the raw hazelnuts in a baking pan, making sure there is enough room in the pan so the hazelnuts are in a single layer. Place the pan in the oven to toast the hazelnuts, checking and stirring the nuts every 2 minutes. The hazelnuts should be fully toasted in 8-10 minutes. Remove the hazelnuts from the oven and allow to cool completely.
Place the hazelnuts in a food processor, and process for about 10 seconds, until they are finely ground. Add the vegetable oil through the feed tube, and process for another 10 seconds until the mixture becomes smooth.
Stop the food processor, remove the lid and add the chocolate chips, cocoa, powdered sugar and vanilla. Close the processor container again, and process until the mixture is smooth and shiny, about 2 minutes.
The chocolate hazelnut spread is ready to eat or use immediately. Store in the refrigerator but bring to room temperature before use.