Position a rack in the center of the oven and heat the oven to 325°F. In a medium bowl, beat the cream cheese and brown sugar with a stand mixer or hand-held mixer on medium speed until smooth and lump-free, about 3 min. Add the pumpkin, cinnamon, ginger, and salt and continue beating until well blended, about 1 min. Add the egg yolk, egg, and vanilla and beat until just incorporated. Sprinkle the chopped crystallized ginger over the batter and stir it in with a rubber spatula.
Use the spatula to scrape the filling into the crust and spread it evenly. Bake the tart until the filling just barely jiggles when the tart pan is nudged, 25 to 30 min. Transfer the tart to a rack and let cool completely. Refrigerate the tart in the pan until chilled and firm, about 3 hours. Garnish with whipped cream and crystallized ginger, if you like.
Photo: Scott Phillips