Preheat oven to 350 degrees. Prepare a large baking sheet with parchment paper or non-stick cooking spray and set aside.
In a large bowl using hand mixer, or in bowl of stand mixer using paddle attachment, beat together the margarine, rice bran oil, and sugar until creamy. Add the egg, and vanilla, and mix to combine.
In a medium bowl, whisk together the flour, potato starch, baking powder and salt. Turn the mixer on low and add dry ingredients to butter/sugar mixture in thirds.
Stir in the cranberries and pistachios.
Drop cookies by rounded Tablespoon fulls onto prepared baking pan.
Bake in preheated oven for 12-15 minutes, until lightly golden brown.
Allow cookies to cool on pan for 5 minutes before transferring to a wire rack to cool completely