Beat the cream cheese until fluffy and smooth. Beat in the sugar. Then add the egg, pumpkin, vanilla, and salt. Mix until smooth. Refrigerate until ready to use.
Cake
Preheat the oven to 350 degrees. Grease a bundt pan and set aside. Mix the flour with the baking powder and soda and set aside. Cream the butter and the sugar together. Scrape the bowl and add the eggs one at a time. Mix in the vanilla and molasses. Add all of the spices and half the flour. Mix and scrape the bowl. Add half the buttermilk. Mix until combined. Repeat with the remaining flour and buttermilk. Pour half of the mixture into the prepared bundt pan. Spoon the pumpkin filling in the center of the cake batter. Top with the remaining batter.
Bake the cake for 45-50 minutes. Allow the cake to cool completely before turning out onto a cake plate. If desired sprinkle with powdered sugar before serving.