Preheat the oven to 350°F. Butter a 15×10" jelly roll pan and set aside. In a large bowl, beat the eggs, sugar, oil, pumpkin and vanilla just until combined. In a medium sized bowl, sift together the flour, baking powder, cinnamon, salt, baking soda and spices. Add to pumpkin mixture and stir just until combined.
Spread the batter in the greased pan. Bake for 25 minutes, or until lightly browned and a toothpick comes clean. Allow to cool.
For the frosting, cream together the cream cheese, butter and vanilla. Gradually add powdered sugar. Beat until smooth and creamy. Add a pinch of salt and cinnamon if desired.
Spread frosting on top of the pumpkin bars with a spatula. Sprinkle with extra cinnamon or pumpkin spice if desired.
Slice into squares. Top with a candy pumpkin if desired.
Pan: You can also use a 9×13″ pan for a thicker cake. Cook for 30-35 minutes.Storage: Store in a covered container in the refrigerator for up to 3 days.