Meanwhile make the pistachio matcha butter. Combine pistachios, matcha green tea powder, and agave nectar in a
food processor or a high-powered blender. Blend until it becomes creamy and butter-like, scraping down the sides as necessary. If you have a high-powered blender (like a VitaMix) this will take a couple of minutes. In a food processor, it will take anywhere between 10 and 20 minutes.