To make pumpkin purée from scratch, cut medium-small sugar pumpkin in half. Scrape out the insides (reserving the pumpkins seeds to toast) and discard. Line a baking sheet with Silpat or foil. Place the pumpkin halves cut side down on the lined baking sheet and bake at 350°F until a fork can easily pierce them, about an hour to an hour and a half. Remove from oven, let cool, scoop out pulp. Alternatively, cut pumpkin into sections and steam in saucepan with a couple inches of water at the bottom, until soft (strain before using). If you want the purée to be extra smooth, press the pulp through a food mill or chinois.
Preheat oven to 425°F. Beat the eggs in a large bowl. Mix in the brown sugar, white sugar, salt, spices-cinnamon, ground ginger, nutmeg, ground cloves, cardamom, and lemon zest.
Mix in pumpkin purée. Stir in cream. Beat together until well mixed. Pour filling into an uncooked pie shell. Bake at a high temperature of 425°F for 15 minutes. Then after 15 minutes, lower temperature to 350°F. Bake for 45 to 55 minutes more, or until a knife inserted in the center comes out clean. (About half-way through the baking, you may want to put foil around the edges or use a pie protector to keep the crust from getting too browned.)
Cool pumpkin pie on a wire rack for 2 hours. Note the pumpkin pie will come out of the oven all puffed up (from the leavening of the eggs), and will deflate as it cools.
Serve with whipped cream.