In the work bowl of a food processor, place walnuts. Pulse 5 times or until coarsely ground.
In a medium bowl, place walnuts, butter, and pumpkin pie spice; coarsely mash. On a sheet of wax paper, spoon butter mixture into a 7-inch log. Fold wax paper over butter mixture. Roll up, tightly twisting ends to seal. Refrigerate until firm. Just before serving, sprinkle sugar in a thin layer on a work surface. Unwrap butter; roll in sugar. Cut chilled butter into desired serving sizes.
Recipe by Cottage Journal at https://thecottagejournal.com/wild-blueberry-sour-cream-pancakes-walnut-spiced-butter/