8 ounces hazelnuts
1 cup powdered sugar
1/3 cup cocoa powder
2 tablespoons hazelnut oil
1 teaspoon vanilla extract
1/8 teaspoon salt
Preheat the oven to 375ºF. Spread the hazelnuts out in a single layer on a baking sheet and roast for 12 to 15 minutes, or until the hazelnuts are brown and fragrant. Rotate baking sheet halfway through baking so the nuts roast evenly. Let hazelnuts cool and transfer to a medium-sized bowl.
Once the hazelnuts are cool enough to handle, transfer hazelnuts to a food processor or blender. Process the hazelnuts for 2 to 5 minutes, or until their oil is released and they form a smooth, loose paste. Scrape down the bowl often. Add the powdered sugar, cocoa powder, hazelnut oil, vanilla extract, and salt. Keep processing until fully incorporated, scraping the bowl down as needed. The mixture will become loose and glossy and resemble a spreadable paste.
Transfer the spread to a jar, and store in the refrigerator or at room temperature for up to 1 month.