Stirring natural peanut butter can be a long sloppy mess as the oil on top more easily spills off than blends into the peanut butter. And it takes a while too. The job goes more quickly and is more thoroughly blended with a single mixer blade running at low speed. Pour off some of the oil into a small bowl. Insert the mixer blade into the peanut butter. Blend, gradually adding all the oil back into the peanut butter. Scrape excess peanut butter off the blade and into the jar.