Line your cookie sheets with parchment paper and preheat the oven to 325 F degrees.
In a standing mixer, thoroughly combine the butter, pumpkin puree, sugar, dark brown sugar, eggs, and vanilla extract.
In a large bowl mix together the flour, cream of tartar, baking soda, ground cinnamon, nutmeg and ginger. Add the dry to the wet ingredients in three parts. Don’t over mix.
Using a medium cookie dough scooper (1.5 tablespoon) place each individual ball of cookie dough on the cookie sheet with a few inches of space in between. Generously sprinkle the tops of each one with the cinnamon, sugar and a white chocolate chip in the center.
Bake for about 12 minutes or until just lightly golden.