In a small bowl, whisk together the flour, pumpkin pie spice and baking soda.
In a medium bowl, with an electric mixer, cream butter and sugar. Beat in pumpkin pie puree. Beat in the eggs and vanilla. Beat in the flour mixture until just combined. Stir in the white chocolate and pecans.
Drop dough by rounded tablespoon 2 inches apart on an ungreased cookie sheet. Bake at 300 degrees F (150 degrees C) for 20-22 minutes until just set.