Drain the cashews and place in a blender with the banana, tofu, sugar, brown sugar, coconut oil, cornstarch, lemon juice, vanilla, orange zest, and sea salt. Blend until completely smooth and no bits of cashew remain, a food processor or strong blender should be able to get the job done.
Set aside 1/2 cup of batter. To the remaining batter, add the pumpkin puree, cinnamon, ginger, and nutmeg and blend until smooth, then pour it into the crust. Randomly spoon dollops of the reserved batter onto the cheesecake. Poke the end of a chopstick into a batter blob and gently swirl to create a marble pattern; repeat with the remaining dollops.
Bake the cheesecake for 45 to 50 minutes. Remove cheesecake halfway through baking and sprinkle on the topping. Return to oven to continue baking. Cheesecake will be done when the top is lightly puffed and the edges of the cake are golden. Remove it from the oven and let cool on a rack for about 20 minutes, then transfer to the refrigerator to complete cooling, at least 3 hours or even better if overnight. To serve, slice the cake using a thin, sharp knife dipped in cold water.