Place sunflower seeds into the jar or bowl of a high-powered blender or food processor, respectively. Pulse the sunflower seeds until they are finely chopped.
Process or blend on a low speed for 1 minute continuously, then stop the machine and scrape down the sides. The sunflower seed will be dry and gritty.
Process or blend on a low speed a second time for 1 minute continuously, then stop the machine and scrape down sides. The sunflower seed butter will start to form a clumpy paste. If using raw sunflower seeds, you may need to add 1-2 tablespoons unflavored oil to facilitate the blending.
Process or blend on a low speed a third time for 1 minute continuously, then stop the machine and scrape down sides. The sunflower seed butter will be thick and grainy at this point. Add more oil, if needed.
Process or blend on a medium speed fourth time for 1 to 2 minutes longer. The sunflower seed butter should be creamy and smooth at this point. It may be hot to the touch, so allow it to cool before transferring to a jar. If using sugar or salt, add it now and process or blend again to combine (I like ¼ cup brown sugar and 1 teaspoon salt).
The sunflower seed butter will keep in a covered container in the refrigerator for several months, but can also be kept at room temperature for a couple of weeks.
