Preheat oven to 350°F (176°C) and roast the hazelnuts for about 15 minutes, watching closely, until the skins have darkened and are starting to peel away from the nut. Shake the pan every 5 minutes to make sure the hazelnuts are evenly roasted.
When the hazelnuts are done roasting, transfer them onto the center of a kitchen towel. Gather the corners of the kitchen towel, enclosing the hazelnuts, and then rub vigorously for 1-2 minutes until the skins fall off. It's fine if not all skins fall off. Pick out the nuts (leaving the skins behind on the towel) and place them into a heavy-duty food processor. Another option is to place the roasted hazelnuts into a mason jar, put the lid on, and then shake the jar vigorously for 1-2 minutes until the skins fall off. Pick out the nuts (leaving the skins behind on the towel) and place them into a heavy-duty food processor.
Process the hazelnuts anywhere between 5 to 15 minutes, until they turn into nut butter. A good way to tell you’re are the right consistency when processing the nuts is when the nut butter starts having an almost oily, sleek or shiny surface. Depending on your food processor, this should take anywhere from 5 to 15 minutes.
Add the cashews, cocoa powder, powdered sweetener, sunflower lecithin, and salt. Process for another 5 minutes or so, until the spread is smooth. As the food processor is running, add the melted coconut oil and melted chocolate (optional).
Store leftover Nutella in an airtight container in the refrigerator for several weeks. The Nutella will thicken when chilled. Simply bring it to room temperature to soften. For longer term storage, freeze in an airtight container for 3 months.
*If you use a granulated sweetener (as opposed to a powdered sweetener), you will need to grind it into a fine powder first.
**Homemade Nutella (without coconut oil) is thinner than regular Nutella. That's because the Nutella thickens as the coconut oil cools. FYI, the amount of palm oil in the original Nutella recipe is ~20%.